Communities around Boston were put on lockdown Friday morning as authorities searched for one of the suspects in the Boston Marathon bombings. [embedgallery id= 137610]
Tamerlan Tsarnaev, 26, the man the FBI labeled "Suspect 1" in the investigation, was killed by law enforcement officers during a shootout overnight, according Reuters.
Dzhokhar Tsarnaev, 19, designated as "Suspect 2," is still on the run and remains a serious threat. The two suspects were reportedly brothers from Chechnya.
Around 10:20 Thursday night, an MIT police officer was shot and killed on campus, the Middlesex County District Attorney said in a statement. An MBTA officer was critically hurt.
A short time later, police received reports of a carjacking by two men who kept their victim inside the car for about half an hour, the statement said.
Police pursued that car to Watertown, where explosives were thrown from the car at police and gunfire was exchanged, the statement said.
"During the exchange of the gunfire, we believe that one of the suspects was struck and ultimately taken into custody. A second suspect was able to flee from that car and there is an active search going on at this point in time," Col. Timothy Alben, superintendent of the Massachusetts State Police, told a news conference.
The first suspect died at Beth Israel Hospital. Doctors said he had gunshot wounds and "blast injuries."
Officials urged people who live in Watertown, Newton, Waltham, Belmont, Cambridge and the Alston/Brighton neighborhoods of Boston to stay inside.
In Watertown, SWAT teams were conducting a door-to-door search. No vehicles were being allowed in or out of the community.
All MBTA service was shut down until further notice. Boston Public Schools and colleges were also closed for the day.