About 12:45 a.m., gunfire broke out between the suspects and police in Watertown. Massachusetts Bay Transit Authority Police Officer Richard H. Donohue was badly wounded in the shootout, but is expected to survive. Tamerlan Tsarnaev also suffered serious injuries and was pronounced dead at Beth Israel Deaconess Medical Center at 1:35 a.m.
His younger brother got away in the car, reportedly running over his brother in his haste, and setting off a chase that led to close police scrutiny of the area. Some 200 spent shells were found afterward.
The brothers had built an arsenal of pipe bombs, grenades and improvised explosive devices and used some of the weapons in trying to make their getaway, said Rep. Dutch Ruppersberger, D-Md., a member of the House Intelligence Committee.
Officials also locked down and later evacuated the University of Massachusetts Dartmouth, a campus about 60 miles from Boston where the younger Tsarnaev is a student. By midafternoon, National Guard helicopters were landing at the campus and off-loading what appeared to be SWAT teams.
Commissioner Davis said that a resident alerted police to the potential hiding site late last night. The neighborhood had been locked down all day, but law enforcement officials advised residents after 6 p.m. that it was safe to go outside. One Franklin Street resident went to check on his boat.
“He happened to notice that the boat didn’t look right, so he looked inside, that’s where he saw the blood and the body,” Franklin Street resident George Pizzuto told ABC.
Franklin Street residents in Watertown heard a flurry of gunshots around 7 p.m. Law enforcement and emergency vehicles arrived with sirens screaming at the scene, setting up a perimeter that was reinforced by the minute Davis said there was an exchange of gunfire and residents heard a number of flash-bang grenades — the final volley of one of the biggest manhunts in American history.