BOSTON, the United States, April 19 (Xinhua) -- Two men sought in the Boston Marathon bombing killed a police officer, wounded another in a firefight and hurled explosive devices at police during their getaway attempt in a night of violence that left one suspect dead and the other on the loose early Friday.
The mayhem began at approximately 10:20 p.m. Thursday local time when police received reports of shots fired on the MIT campus. At 10:30 p.m. local time, a campus police officer was found fatally shot in his vehicle.
The Middlesex County district attorney said in a statement Friday that the suspected bombers first tried to rob a convenience story in Cambridge, across the river from Boston. They then went to the MIT campus where they shot at the police officer several times.
Afterwards, the two hijacked a Mercedes Benz and eventually let the driver out at a gas station in Cambridge. He was not injured.
The search for the vehicle led to a chase that ended in Watertown. Police said the suspects threw explosive devices from their car and exchanged gunfire with officers. A transit police officer was seriously injured during the chase, authorities said.
In Watertown, witnesses reported hearing multiple gunshots and explosions at about 1 a.m. Friday local time. Dozens of police officers and FBI agents were in the neighborhood and a helicopter circled overhead.
The captured bombing suspect was confirmed dead at an area hospital from multiple gunshot wounds, while the second, a young man described as an armed and dangerous terrorist, remained at large.
Doctors at a Boston hospital where the captured suspect was taken and later died said they treated a man with a possible blast injury and multiple gunshot wounds.
"One suspect dead. One at large," Boston Police Commissioner Ed Davis said on his official Twitter account.
A massive manhunt launched by the FBI and hundreds of state and local police officers for the second bomber continued into Friday.
Police urged people in Watertown, Cambridge and other western suburbs, as well as some western neighborhoods of Boston, to stay indoors as the search continued.
"We believe this to be a terrorist. We believe this to be a man who has come here to kill people," Davis said.
In the pursuit of the suspect, another officer was seriously injured and transported to an area hospital.
To prevent the suspect from escaping, police enlarged their search area to all of Boston.
Authorities suspended public transportation, including buses, subways, trolleys, commuter trains and boats, in the Boston region during the search.
The violence and manhunt began only a few hours after the FBI released photos and videos of the two suspected bombers, who were seen carrying backpacks as they walked near the marathon finish line.
Monday's bombings at one of the world's most storied races killed three people and wounded more than 180 others. Authorities released the images to an effort to have the public help locate the suspects.
U.S. President Barack Obama was briefed overnight on the bombing investigation and ongoing manhunt.
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