A violent crime spree across Greater Boston that took the lives of a campus police officer and one of the suspects in the Marathon bombings morphed into a desperate door-to-door search for a man believed to be the second bomber in Monday’s dual blasts.
After a string of explosions and volleys of gunfire that seriously injured a transit officer, police cordoned off much of Watertown, Mass. Residents were ordered to “shelter in place” and not trust anyone they might see other than uniformed officers.
A Massachusetts State Police public information officer told HuffPost reporter Michael McLaughlin, "We believe this to be a terrorist, we believe he came here to kill people."
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At daybreak, law enforcement planned to launch a house-to house search through much of Watertown as they sought one half of the duo believed to have killed three and wounded more than 170 at the Boston Marathon finish line on Monday.
A chaotic Thursday night across Cambridge and Watertown started at 10:30 p.m. with a convenience store holdup that led to the shooting of an MIT campus officer who died later from multiple gunshot wounds.
Police sped away from the campus crime scene amid reports of an armed carjacking of a Mercedes SUV nearby.
The breakneck pursuit of the stolen car led to Watertown, where suspects detonated explosives in the direction of officers before exchanging gunfire.
“I heard three loud bangs,” a witness told HuffPost. “It sounded like a car being dropped on the ground.”
The threat to anyone in the area was so serious that the police planned robocalls to warn residents, CNN reported.
Hundreds of officers drawn from many departments spent hours looking for additional explosives, criminal evidence and, perhaps most importantly, a man deemed to be armed and dangerous.
One suspect died in the exchange of gunfire with police in Watertown. Neither suspects' identity was released.
The long night followed a day in which the FBI released video footage and photos of the baseball cap-wearing pair seen carrying suspicious backpacks which they dropped at the Boylston Street finish line.