Boston: one suspected Boston bomber shot and killed, other still on the loose

Via CBS News:

A law enforcement official told CBS News the two suspected bombers have been preliminarily identified. They are believed to be from Chechnya or Turkey. They have been in the United States a little over a year. The two men are not students. They are legal permanent residents of the U.S.

The sources said the two are brothers, 19 and 20.

One has been identified as Dzhokhar A. Tsarnaev of Cambridge, Mass., known as the man in the white hat from the marathon surveillance footage, CBS News reports. The suspect who was killed has been identified as Tamerlan Tsarnaev, CBS News reports.

State Department records helped the FBI identify the suspects, CBS News’ Bob Orr reports.

Boston Police Commissioner Edward Davis says he is “armed and dangerous.”

The Boston Globe is reporting:

One suspect in Monday’s Boston Marathon bombings has been captured, according to an official with knowledge of the investigation. Another remains on the loose in Watertown after a firefight with police. Authorities have established a 20-block perimeter as they search for him.

A scene of chaos descended on Cambridge and Watertown late Thursday night and early Friday morning, as police confirmed an MIT police officer was shot and killed, and an apparent carjacking led police on a wild chase into Watertown. Witnesses in Watertown said they heard explosions. Police officers were screaming about improvised explosive devices.

Authorities would not comment on whether the events were connected to Monday’s Boston Marathon bombings. At least one of the suspects in Watertown appeared to be a man in his 20s. FBI agents were on the scene in Watertown. The FBI source said early Friday it is “too early to speculate” on a relation to the Marathon bombing.

Via NBC News.

Law enforcement sources said the suspects have international links and have been in the country legally for about a year. The suspects approached the MIT officer and shot him in head, the sources said. The two then stole the MIT officer's cruiser, robbed a nearby 7-11 and carjacked a Mercedes SUV, briefly kidnapping the driver, the sources said. At various points, the suspects threw explosives out the window of the moving car. The dead suspect had an improvised explosive device strapped to his chest and the law enforcement sources warned that the suspect on the run may as well.

 (via JMG)