Suspect in murder of MIT cop dead, 2nd suspect, tied to Boston bombing, at large

One of two suspects in the shooting of a Massachusetts Institute of Technology police officer has died and a massive manhunt is underway for another, who is believed to be tied to the Boston Marathon bombing.

Boston Police Commissioner Ed Davis said early Friday on Twitter that one of the two suspects in that officer's shooting was killed. He said the at-large suspect, labeled by the FBI as "suspect two" in the marathon bombing, was "armed and dangerous."

The Middlesex district attorney said the two men are suspected of killing the MIT police officer on campus late Thursday, then stealing a car at gunpoint and later releasing its driver unharmed. Hours earlier, police had released photos of the marathon bombing suspects and asked for the public's help finding them.

The suspects threw explosives from the car as police followed it into Watertown, according to the district attorney's news release. The suspects and police exchanged gunfire, and one of the suspects was critically injured and later died while the other escaped.

Earlier Friday, police were working to apprehend a young male with a hat on who was reportedly pulling on vehicle doors, according to police scanner traffic.

An FBI official told Fox News that one person was in custody and an officer was down but said it was too early to tell if the police activity in Watertown or the MIT shooting were related to the Boston Marathon bombing.

Dozens of officers and National Guard members descended on Watertown shortly after the shooting outside a building on MIT's campus in Cambridge, according to the Associated Press.

Authorities were calling for somebody to get on the ground and put their hands up and a loud thud was heard after someone shouted "fire in the hole," the news agency reported.

Witnesses told The Associated Press they heard 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 told news agency, "The incident in Watertown did involve what we believe to be explosive devices possibly, potentially, being used against the police officers."

Fox News reporters on the scene cannot yet confirm these reports.

Earlier Friday, Cambridge police and the Middlesex District Attorney's office said the MIT officer was responding to a report of a disturbance when he was shot multiple times late Thursday. He later died at a hospital. His name was not immediately released.

Procopio said the shooting took place about 10:30 p.m. outside an MIT building. The area was cordoned off and surrounded by responding law enforcement agencies, according to a posting on the university's website.

The university described the situation late Thursday as "active and extremely dangerous." People were urged to stay away from the Stata Building, a mixed use building with faculty offices, classrooms and a common area.

The shooting came little more than three days after the twin bombings on the Boston Marathon that killed three people, wounded more than 180 others and led to an increase in security across the city.

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