Terror manhunt shuts down parts of Boston after shootings, chase

WATERTOWN, Mass. -- The manhunt for the remaining Boston Marathon bombings suspect left much of the city shut down on Friday, hours after the other suspect was killed in a shootout with police.

President Obama was briefed on the situation, officials said.

Police directly linked the two suspects to Monday's marathon bombings, which left three dead and more than 170 wounded.

As police went door to door in Watertown, where the suspects were tracked after a Thursday night carjacking near MIT, residents were told to stay inside and not to open the door except for a police officer.

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Gov. Deval Patrick ordered the city's mass transit suspended.

Vehicle traffic also was barred in and out of Watertown, police said at an early morning news briefing. Those who work in the area were told to stay home, as were residents of several nearby communities.

Harvard, MIT, Boston College and other universities and public schools said they would be closed Friday for safety reasons.

Authorities said the manhunt began when an MIT police officer was shot to death on campus after responding to a disturbance. Officials said he had multiple gunshot wounds.

Soon after, two suspects carjacked an SUV nearby, officials said. As officers pursued the suspected carjackers to Watertown, the suspects tossed explosives out of the car and fired at officers, officials said.

Suspect No. 1 from the marathon bombings -- who was seen in surveillance video wearing a black hat -- was declared dead at Beth Israel Hospital early Friday morning with gunshot and blast wounds after the early-morning battle, doctors said.

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A transit police officer was also shot and seriously injured, authorities said.

Suspect No. 2, who was seen wearing a white cap, was still at large. Police described him as a terrorist who was armed and dangerous.

The MIT shooting happened about five hours after the FBI released photos of the two suspects in the case and asked for the public's help in identifying them.

About 2:30 a.m. EDT, the FBI also released new photos of both suspects (shown below).

The suspects still have not been identified.

The Boston Police Department released the following photo of the man thought to be Suspect No. 2: