In Watertown, Mass., police in tactical gear search for a suspect in the… (Matt Rourke / Associated…)
The two suspects in last week's Boston Marathon bombing weren't licensed to have guns, the Cambridge, Mass., Police Department confirmed Sunday.
Dzhokhar Tsarnaev, 19, who was captured after a gun battle with police Friday, wasn't old enough to be licensed to own a gun in Massachusetts. The minimum legal age is 21.
His older brother, Tamerlan Tsarnaev, 26, who was fatally wounded hours earlier, never had a license to own or carry a gun in Cambridge, where the pair shared an apartment, Cambridge Police spokesman Dan Riviello told the Los Angeles Times. It's unclear whether he ever applied for a license.
The pair's deadly, chaotic showdown with police that began Thursday night continued to come into focus Sunday as investigators plied through the brothers' lives before the bombing and their actions afterward.
FULL COVERAGE: Boston Marathon attack
About five hours after federal investigators published photos of the the two suspects taken at the Boston Marathon, police say, they killed a Massachusetts Institute of Technology police officer Thursday night and carjacked a Mercedes SUV nearby.
Cambridge Police told The Times that the Mercedes driver escaped when the brothers went inside a Shell gas station on Memorial Drive in Cambridge to buy snacks.
The unidentified driver fled to another gas station to call police.
Sometime later, Boston Police Commissioner Ed Davis told CNN, a police officer began following the Mercedes with the emergency lights off to wait for backup when the brothers stopped their car.
"They aggressively alighted from the car," Davis said. "They stopped their vehicle, they just stopped when they saw the car and attempted to get the officer.”
A hectic gun battle ensued, with the brothers and the responding officers trading more than 200 shots, Davis said. The brothers had three guns, police said. Further details about those guns have not been released.
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Dzhokhar Tsarnaev ran over his wounded older brother when police were about to arrest him, Davis said, though it has not yet been determined what caused Tamerlan's death. He was had gunshot and blast wounds.
An officer was critically wounded in the showdown.
The city of Boston was locked down Friday while officers searched for Dzhokhar Tsarnaev. By early evening, police lifted the lockdown, and a Watertown resident noticed that the cover was loose on the boat he stores in his backyard. As he tried to put it back on he noticed the cover was ripped and had blood on it. He lifted the cover and saw what he thought was a bloody body, Davis told CNN.
“All of a sudden, the body moved,” Davis said, and the resident alerted authorities.
A federal official said Dzhokhar Tsarnaev had been shot in the neck, complicating authorities' efforts to speak to him in the hospital.
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Dzhokhar Tsarnaev remained hospitalized Sunday with a team of FBI interrogators standing by to interview him, Davis said.
He wouldn't confirm whether the brothers had outside help, but he said he believed they were the primary suspects in the bombing, which killed three people and left more than 170 injured.