Shortly after the fatal shooting of a police officer on the campus of Massachusetts Institute of Technology Thursday night, a second shooting incident was reported in Watertown, Mass.
The Boston Globe reported via Twitter that one of the suspects in the Boston Marathon bombing had been caught, and another was on the loose after a firefight with police.
Chatter on the police scanner revealed confusion on the scene as officers reported gunfire, explosions and chaos at the intersection of Laurel and Dexter Streets. Heavily armed officers from Homeland Security have been spotted in the area, as have members of the FBI and National Guard. Helicopters are currently using search lights to illuminate the darkened neighborhood.
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Larry Victor, a dentist in Watertown, told The Huffington Post that he heard dozens of shots and at least two explosions.
In response, all police units have been ordered to retreat to a perimeter being set up near Auburn, Walnut & School Streets. Officers entering the perimeter were ordered to turn off their cellphones. A robot has been brought in to investigate the scene for explosives.
Andrew Kitzenburg of Watertown told the New York Times that he observed a confrontation from a third floor window. He saw two men in jackets engaging in "constant gunfire" with police officers.
The shooters tried to detonate a bomb. “They lit it, still in the middle of the gunfire, and threw it. But it went 20 yards at most," Kitzenburg told the paper.
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WATERTOWN, Mass. — A tense night of police activity that left a university officer dead on campus just days after the Boston Marathon bombings and amid a hunt for two suspects caused officers to converge on a neighborhood outside Boston, where residents heard gunfire and explosions.
The chaos in Watertown, about 10 miles west of Boston, occurred just hours after a Massachusetts Institute of Technology police officer was shot and killed on campus. It was unclear if the outbursts of violence were related. No arrests had been made in the officer's fatal shooting, and a manhunt was on for the shooter.
The officer had been responding to report of a disturbance Thursday night when he was shot multiple times, according to a statement from the Middlesex district attorney's office and Cambridge police. It said there were no other victims.
In Watertown, witnesses reported hearing multiple gunshots and explosions at about 1 a.m. Friday. Dozens of police officers and FBI agents were in the neighborhood and a helicopter circled overhead.
State police spokesman David Procopio said, "The incident in Watertown did involve what we believe to be explosive devices possibly, potentially, being used against the police officers."
Boston cab driver Imran Sais said he was standing on a street corner at a police barricade across from a diner when he heard an explosion.
"I heard a loud boom and then a rapid succession of pop, pop, pop," he said. "It sounded like automatic weapons. And then I heard the second explosion."
He said he could smell something burning and advanced to check it out but area residents at their windows yelled at him, "Hey, it's gunfire! Don't go that way!"
MIT said right after the 10:30 p.m. shooting that police were sweeping the campus in Cambridge and urged people to remain indoors. They urged people urged to stay away from the Stata Building, a mixed-use building with faculty offices, classrooms and a common area.
Hours later, MIT, which has about 11,000 students, said the campus was clear but the shooter was still on the loose.
This is a developing story....