Two explosions near the finish line of the Boston Marathon on April 15 killed three people and wounded scores. Authorities launched a massive manhunt for two suspects seen on surveillance video. A look at the basics of the case:

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NEW DEVELOPMENTS

Bombing suspect Dzhokhar Tsarnaev was hospitalized Saturday in serious but stable condition after having been found wounded and bloody the night before hiding in a boat parked behind a home in Watertown, a Boston suburb authorities had shut down to conduct house-by-house searches.

U.S. officials said a special interrogation team for high-value suspects would question Tsarnaev without reading him his Miranda rights, invoking a rare public-safety exception triggered by the need to protect police and the public from immediate danger. The American Civil Liberties Union said it was concerned about that. It said the exception applies only when there's a continued threat to public safety and is "not an open-ended exception" to the Miranda rule, which guarantees a suspect the right to remain silent and the right to an attorney.

Federal public defenders in Massachusetts have agreed to represent Tsarnaev and said they expect to do so after he is charged. There was no immediate word on when or with what crimes Tsarnaev might be charged, but the most serious charge available to federal prosecutors would be the use of a weapon of mass destruction to kill people, which carries a possible death sentence upon conviction.

The FBI said a foreign government told it in early 2011 about information that Dzhokhar Tsarnaev's older brother, Tamerlan Tsarnaev, was a follower of radical Islam.

According to the FBI, the foreign government said Tamerlan Tsarnaev had changed drastically since 2010 as he prepared to leave the United States to join unspecified underground groups. The FBI says it interviewed him and relatives and didn't find any terrorism activity.

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HOW THE SITUATION UNFOLDED

Surveillance tape late Thursday showed Dzhokhar Tsarnaev, Suspect No. 2, at a gas station. The two suspects fatally shot a university police officer, authorities say. They carjacked a man, released him and got involved in a chase with police that resulted in explosives being thrown from their car and an exchange of gunfire, authorities say. Tamerlan Tsarnaev, Suspect No. 1, was wounded and died later at a hospital.

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PUBLIC REACTION

After the death of one suspect and the capture of the other, people in Boston and its western suburbs thanked police, cheered, applauded and set off fireworks. Later, they gathered in silence near the site of the bombings to remember the victims. Some cried. Some wrapped themselves in American flags.

"Now I feel a little safer," Boston resident Beth Lloyd-Jones said.

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THE SUSPECTS

Law enforcement officials and family members have identified the brothers as ethnic Chechens who had lived in Dagestan, in southern Russia. The brothers had been in the United States for about a decade and lived near Boston, an uncle said. Dzhokhar Tsarnaev, whose father has called him a "true angel," is a 19-year-old student at the University of Massachusetts at Dartmouth. Tamerlan Tsarnaev was a 26-year-old boxer. Their uncle Ruslan Tsarni called them "losers."

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THE MARATHON EXPLOSIONS

Two bombs exploded about 10 seconds and 100 yards apart in Boston's Copley Square, near the finish line of the marathon. An 8-year-old boy, a 29-year-old woman and a 23-year-old graduate student from China were killed, and more than 180 people were wounded. The explosions occurred about four hours into the race and two hours after the winners had crossed the finish line, but thousands of runners were still on the course.

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THE BOMBS

Authorities have said they believe the bombs used were fashioned out of ordinary kitchen pressure cookers packed with explosives, nails, ball bearings and metal shards. They say the bombs were hidden in backpacks and left on the ground.

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  • Police Leave The Scene After Capturing Suspect

    Members of a police S.W.A.T. team exit Franklin Street moments after 19-year-old bombing suspect Dzhokhar A. Tsarnaev was apprehended on April 19, 2013 in Watertown, Massachusetts. A manhunt for a Tsarnaev ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts.

  • Relieved Police Officers After Suspect's Capture

    Two police officers laugh while securing the area around Franklin Street on April 19, 2013 in Watertown, Massachusetts. A manhunt for a suspect in the Boston Marathon bombing, Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts.

  • Watertown Residents Celebrate

    Residents applaud after the capture of the second of two suspects wanted in the Boston Marathon bombings April 19, 2013 in Watertown, Massachusetts.

  • Media Interview Cops After Suspect Captured

    A SWAT team member is followed by reporters and a celebrating crowd after the successful operation to capture 19-year-old bombing suspect Dzhokhar A. Tsarnaev on April 19, 2013 in Watertown, Massachusetts.

  • Watertown Residents Waiting As Police Closed In On Suspect

    Residents await the capture of the second of two suspects wanted in the Boston Marathon bombings April 19, 2013 in Watertown, Massachusetts. Thousands of heavily armed police staged an intense manhunt for a Chechen teenager suspected in the Boston marathon bombings with his brother, who was killed in a shootout.

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    Resident Rosie Meyer, who said she heard gunshots, reacts while watching police respond on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly Chechen of origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Mario Tama / Getty Images)

  • Suspect No, 2's Last Stand

    Police officers guard the entrance to Franklin street where there is an active crime scene search for the suspect in the Boston Marathon bombings, Friday, April 19, 2013, in Watertown, Mass. Gunfire erupted Friday night amid the manhunt for the surviving suspect in the Boston Marathon bombing, and police in armored vehicles and tactical gear rushed into the Watertown neighborhood in a possible break in the case. (Matt Rourke / AP)

  • Suspect No, 2's Last Stand

    Mimi de Quesada, of Watertown, Mass., reacts while standing by her home in the wake of the sound of shots fired in Watertown, Mass., Friday, April 19, 2013, as a massive search continued for one of two suspects in the Boston Marathon bombings. De Quesada said she had just come out to enjoy the day when the shots rang out about two blocks form her home. A second suspect died in the early morning hours after an encounter with law enforcement. (Craig Ruttle / AP)

  • Suspect No, 2's Last Stand

    An officer evacuates a child away from an area where a suspect is hiding on Franklin St., on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    People watch as police search for suspect in the Boston Marathon bombings, Friday, April 19, 2013, in Watertown, Mass. Gunfire erupted Friday night amid the manhunt for the surviving suspect in the Boston Marathon bombing, and police in armored vehicles and tactical gear rushed into the Watertown neighborhood in a possible break in the case. (Matt Rourke / AP)

  • Suspect No, 2's Last Stand

    Many different law enforcement agencies descend on an area around Franklin Street on April 19, 2013 in Watertown, Massachusetts. After a car chase and shootout with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Jared Wickerham / Getty Images)

  • Suspect No, 2's Last Stand

    Police converge near the scene where it was believed 19-year-old bombing suspect Dzhokhar A. Tsarnaev is in hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly Chechen of origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Spencer Platt / Getty Images)

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    People react while watching police respond to a reported shooting on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly Chechen of origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Mario Tama / Getty Images)

  • Suspect No, 2's Last Stand

    Members of a police S.W.A.T. team run to the scene where it was believed 19-year-old bombing suspect Dzhokhar A. Tsarnaev is in hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly of Chechen origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Spencer Platt / Getty Images)

  • Suspect No, 2's Last Stand

    Police converge near the scene where it was believed 19-year-old bombing suspect Dzhokhar A. Tsarnaev is in hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly of Chechen origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Spencer Platt / Getty Images)

  • Suspect No, 2's Last Stand

    Family members who fled the scene where it was believed 19-year-old bombing suspect Dzhokhar A. Tsarnaev is in hiding are comforted on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly of Chechen origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Spencer Platt / Getty Images)

  • Suspect No, 2's Last Stand

    Members of a police S.W.A.T. team run to the area where it was believed 19-year-old bombing suspect Dzhokhar A. Tsarnaev is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police last night, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly of Chechen of origin, are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Spencer Platt / Getty Images)

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • Suspect No, 2's Last Stand

    Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Darren McCollester / Getty Images)

  • The Manhunt Continues

    A woman carries a girl from their home as a SWAT team searching for a suspect in the Boston Marathon bombings enters the building in Watertown, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during their getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist. (AP Photo/Charles Krupa)

  • Manhunt For Bombing Suspect No. 2

    Police in tactical gear surround an apartment building while looking for a suspect in the Boston Marathon bombings in Watertown, Mass., Friday, April 19, 2013. All residents of Boston were ordered to stay in their homes Friday morning as the search for the surviving suspect in the marathon bombings continued after a long night of violence that left another suspect dead. (AP Photo/Charles Krupa)

  • Manhunt For Bombing Suspect No. 2

    A police officer evacuates a shoeless man holding a child as members of law enforcement conduct a search for a suspect in the Boston Marathon bombings, Friday, April 19, 2013, in Watertown, Mass. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during a getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist. (AP Photo/Matt Rourke)

  • Manhunt For Bombing Suspect No. 2

    Residents look out a window as officials inspect an apartment building in Watertown, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during their getaway attempt in a long night of violence that left one of them dead and another still at large Friday. (AP Photo/Julio Cortez)

  • Manhunt For Bombing Suspect No. 2

    Heavily armed police officers do house to house searches the neighborhoods of Watertown, Mass. Friday, April 19, 2013, as a massive search continued for one of two suspects in the Boston Marathon bombing. A second suspect died in the early morning hours after an encounter with law enforcement. (AP Photo/Craig Ruttle)

  • Manhunt For Bombing Suspect No. 2

    Police in tactical gear conduct a search for a suspect in the Boston Marathon bombings, Friday, April 19, 2013, in Watertown, Mass. The bombs that blew up seconds apart near the finish line of the Boston Marathon left the streets spattered with blood and glass, and gaping questions of who chose to attack and why. (AP Photo/Matt Rourke)

  • Manhunt For Bombing Suspect No. 2

    Tactical teams exit an apartment building while searching for a suspect in the Boston Marathon bombings in Watertown, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during a getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist. (AP Photo/Charles Krupa)

  • Manhunt For Bombing Suspect No. 2

    KRON 4 Coverage of the Watertown Mass. Manhunt

  • Manhunt For Bombing Suspect No. 2

    A police officer in tactical gear conducts a search for a suspect in the Boston Marathon bombings, Friday, April 19, 2013, in Watertown, Mass. The bombs that blew up seconds apart near the finish line of the Boston Marathon left the streets spattered with blood and glass, and gaping questions of who chose to attack and why. (AP Photo/Matt Rourke)

  • Manhunt For Bombing Suspect No. 2

    Police continue to patrol the neighborhoods of Watertown, Mass. Friday, April 19, 2013, as a massive search continued for one of two suspects in the Boston Marathon bombing. A second suspect died in the early morning hours after an encounter with law enforcement. (AP Photo/Craig Ruttle)

  • Police Search For Suspect

    A police officer with gun drawn searches for a suspect on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. It's not clear whether the shootings are related or whether either are related to the Boston Marathon bombing.

  • Manhunt For Bombing Suspect No. 2

    The search continues April 19, for the second suspect in the Boston Marathon bombings.

  • Manhunt For Bombing Suspect No. 2

    Man being taken into custody on Nichols Ave and Quimby. Police overheard saying "he has shit all in his pockets."

  • Manhunt For Bombing Suspect No. 2

    A neighbor is escorted to safety as police surround a home while searching for a suspect in the Boston Marathon bombings in Watertown, Mass., Friday, April 19, 2013. The two suspects in the Boston Marathon bombing killed an MIT police officer and hurled explosives at police in a car chase and gun battle overnight that left one of them dead and his brother on the loose, authorities said Friday. (AP Photo/Charles Krupa)

  • Cops In Bullet Proof Vests

    Cops suiting up with bullet proof vests in Watertown.

  • Reports Of Shooting, Explosions In Watertown

    A vehicle carrying officers in tactical gear arrives at the Watertown neighborhood of Boston, Friday, April 19, 2013. Dozens of officers and National Guard members are in Watertown, where television outlets report that gunfire and explosions have been heard.

  • Officers Arrive In Watertown

    Officers wearing tactical gear arrive at the Watertown neighborhood of Boston, Friday, April 19, 2013.

  • A girl looks out the window of her family's home as a SWAT team drives through her neighborhood while searching for a suspect in the Boston Marathon bombings in Watertown, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during their getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist. (AP Photo/Charles Krupa)

  • FBI On Scene In Watertown

    An FBI official arrives at the Watertown neighborhood of Boston, Friday, April 19, 2013.

  • Police Establishing Perimeter

    Boston Police are setting up perimeter tape across Nichols Avenue right now.

  • Police officers stand guard in a staging area as nearby officials conducts a search for a suspect in the Boston Marathon bombings, Friday, April 19, 2013, in Watertown, Mass. The two suspects in the Boston Marathon bombing killed an MIT police officer and hurled explosives at police in a car chase and gun battle overnight that left one of them dead and his brother on the loose, authorities said Friday. (AP Photo/Matt Rourke)

  • Manhunt For Bombing Suspect No. 2

    Boston Police chief on the scene in Boston's Watertown neighborhood.

  • Christina Wilkie Reports From Watertown

  • FBI Agents Arrive In Watertown

    A half-dozen FBI agents just arrived at the Nichols Ave perimeter. At least one in a bulletproof vest.

  • Raw Shooting at MIT Watertown

    A NewsCenter 5 viewer sent in uncut video of a shootout between police and at least one suspect in the streets of Watertown, Mass.