PARIS (AP) -- Paris reeled on Saturday as the death toll from Friday's massive, coordinated terror attacks continued to rise. One-hundred and twenty-nine people were confirmed dead and 352 injured -- 99 critically -- after suicide bombings near France's national stadium and a hostage-taking slaughter inside a concert hall.
At least one American, 23-year-old student Nohemi Gonzalez, was killed. She was in Paris on an exchange program from the California State University, Long Beach.
Paris prosecutor Francois Molins said three teams of assailants appear to have worked in coordination with each other, with seven attackers wearing suicide vests and carrying Kalashnikov rifles. He said that the attackers at the Bataclan, the concert hall where 89 people were killed and hundreds taken hostage, mentioned Syria and Iraq during the siege.
One of the suicide bombers involved in the attacks has been identified as Ismael Omar Mostefai by a member of the French Parliament, CNN reported.
The Islamic State claimed responsibility for the attacks, which were the deadliest in France since World War II, issuing an online statement in Arabic and French circulated by the group's supporters. It was not immediately possible to confirm the authenticity of the admission, which bore the group's logo and resembled previous verified statements from the group. French President Francois Hollande vowed to attack the Islamic State without mercy.
Information about the attackers and possible accomplices trickled in on Saturday.
Police identified one of the bombers as a young Frenchman who had been flagged by authorities for his ties to Islamic extremism.
Reuters reported that a Syrian passport was found near the bodies of one of the bombers and that the holder of the passport passed through Greece in October.
A spokesman for Belgium's Justice Minister said on Saturday that authorities had made several arrests in the capital, Brussels, in connection with the attacks. Koen Geens explained that one of the cars used during Friday's assaults had Belgian license plates and that receipts found inside the car were issued in a Brussels neighborhood.
A 51-year-old man arrested in Germany last week with weapons in his car may also be linked to the attacks, the governor of Bavaria said Saturday.
The prosecutor's office spokeswoman, Agnes Thibault-Lecuivre, said authorities couldn't rule out the possibility that other militants involved in the attack remained at large.
French President Francois Hollande vowed to attack the Islamic State without mercy.
Hollande, who declared three days of national mourning and raised the nation's security to its highest level, called the carnage "an act of war that was prepared, organized, planned from abroad with internal help." He said that France -- which is already bombing IS targets in Syria and Iraq as part of the U.S.-led coalition and has troops fighting militants in Africa -- "will be merciless toward the barbarians of [the] Islamic State group."
World leaders united in sympathy and indignation, New York police increased security measures and people worldwide reached out to friends and loved ones in France as Parisians lined up in droves to donate blood.
The White House said there was no "specific or credible threat" to the U.S. after the attacks.
The violence raised questions about security for the millions of tourists who come to Paris and for world events routinely hosted in the normally luminous capital, where troops were deployed to support police trying to restore order.
One of Europe's most heavily visited tourist attractions, the Disneyland Paris theme park east of the city, announced it would not open for business Saturday, a rarity. It billed the move as a matter of sympathy, not security, and said in a statement it would remain closed "in light of the recent tragic events in France and in support of our community and the victims of these horrendous attacks."
Reflecting fears in other European capitals of the risk of coordinated or copycat attacks, the British government scheduled a meeting of its own emergency COBRA intelligence committee overseen by Prime Minister David Cameron. Italy said it, too, was raising security levels at borders and major public places.
Friday night's militants launched at least six gun and bomb attacks in rapid succession on apparently indiscriminate civilian targets.
Three suicide bombs targeted spots around the national stadium, the Stade de France, where Hollande was watching an exhibition soccer match. Fans inside the stadium recoiled at the sound of explosions but the match continued amid rising spectator fears.
The Wall Street Journal reported that one of the suicide bombers had tickets to the match, but was turned away when his explosives were discovered, at which point he blew himself up.
Around the same time, fusillades of bullets shattered the clinking of wine glasses in a trendy Paris neighborhood as gunmen targeted a string of cafes, which were crowded on an unusually balmy November night. At least 37 people were killed, according to Paris Prosecutor Francois Molins.
The attackers next stormed the Bataclan concert hall, which was hosting the American rock band Eagles of Death Metal. They opened fire on the panicked audience and took members hostage. As police closed in, three detonated explosive belts, killing themselves, according to Paris police chief Michel Cadot.
Another attacker detonated a suicide bomb on Boulevard Voltaire, near the music hall, the prosecutor's office said.
The Bataclan was the scene of the worst carnage.
Graphic and disturbing video shot from an apartment balcony and posted on Le Monde's website Saturday captured some of that horror as dozens of people fled from gunfire outside the Bataclan down a passageway to a side street.
In the video, at least one person lies writhing on the ground as scores more stream past, some of them bloodied or limping. The camera pans down the street to reveal more fleeing people dragging two bodies along the ground. A woman and two others can be seen clinging to upper-floor balcony railings in an apparent desperate bid to stay out of the line of fire.
Le Monde said its reporter who filmed the scene from his apartment balcony, Daniel Psenney, was shot in the arm when he stopped filming and went downstairs to help someone who had collapsed in the alley.
Sylvain, a tall, sturdy 38-year-old concertgoer, collapsed in tears as he recounted the attack, the chaos and his escape during a lull in gunfire.
"I was watching the concert in the pit, in the midst of the mass of the audience. First I heard explosions, and I thought it was firecrackers.
"Very soon I smelled powder, and I understood what was happening. There were shots everywhere, in waves. I lay down on the floor. I saw at least two shooters, but I heard others talk. They cried, 'It's Hollande's fault.' I heard one of the shooters shout, 'Allahu Akbar,'" Sylvain told The Associated Press. He spoke on the condition that his full name not be used out of concern for his safety.
He was among dozens of survivors offered counseling and blankets in a municipal building set up as a crisis center.
Jihadis on Twitter immediately praised the attackers and criticized France's military operations against Islamic State extremists.
Hollande declared a state of emergency and announced renewed border checks along frontiers that are normally open under Europe's free travel zone.
In a televised Friday night address he appealed to citizens to maintain "a determined France, a united France, a France that joins together and a France that will not allow itself to be staggered, even if today there is infinite emotion faced with this disaster, this tragedy, which is an abomination, because it is barbarism."
President Barack Obama, speaking to reporters in Washington, decried an "attack on all humanity."
A U.S. official briefed by the Justice Department says intelligence officials were not aware of any threats before Friday's attacks.
Paris is expected to host 80 heads of state, including Obama, for a climate summit in two weeks. In June, France is scheduled to host the European soccer championship -- with the Stade de France a major venue.
And Paris-based UNESCO is expecting world leaders Monday for a forum about overcoming extremism. Iranian President Hassan Rouhani canceled a trip because of Friday's attacks. Hollande canceled a planned trip to this weekend's G-20 summit in Turkey.
France has been on edge since January, when Islamic extremists attacked the satirical newspaper Charlie Hebdo, which had run cartoons of the Prophet Muhammad, and a kosher grocery. Twenty people died in those attacks, including three shooters.
France has seen several smaller-scale attacks or attempted attacks this year, including on a high-speed train in August when American travelers overpowered a heavily armed man.
French authorities are particularly concerned about the threat from hundreds of French Islamic radicals who have traveled to Syria and returned home with skills to mount attacks.
"The big question on everyone's mind is: Were these attackers -- if they turn out to be connected to one of the groups in Syria -- were they homegrown terrorists or were they returning fighters?" said Brian Michael Jenkins, a terrorism expert and senior adviser to the president of the Washington-based RAND Corporation. "That will be a huge question."
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