During the long night of violence leading up to the capture, the Tsarnaev brothers killed an MIT police officer, severely wounded another lawman and took part in a furious shootout and car chase in which they hurled explosives at police from a large homemade arsenal, authorities said.
Watertown Police Chief Edward Deveau said one of the explosives was the same type used during the Boston Marathon attack, and authorities later recovered a pressure cooker lid that had embedded in a car down the street. He said the suspects also tossed two grenades before Tamerlan ran out of ammunition and police tackled him.
But while handcuffing him, officers had to dive out of the way as Dzhokhar drove the carjacked Mercedes at them, Deveau said. The SUV dragged Tamerlan's body down the block, he said. Police initially tracked the escaped suspect by a blood trail he left behind a house after abandoning the Mercedes, negotiating his surrender hours later in the boat.
Chechnya, where the Tsarnaev family has roots, has been the scene of two wars between Russian forces and separatists since 1994. That spawned an Islamic insurgency that has carried out deadly bombings in Russia and the region, although not in the West.
Investigators have not offered a motive for the Boston attack. But in interviews with officials and those who knew the Tsarnaevs, a picture has emerged of the older one as someone embittered toward the U.S., increasingly vehement in his Muslim faith and influential over his younger brother.
The Russian FSB intelligence service told the FBI in 2011 about information that Tamerlan Tsarnaev was a follower of radical Islam, two law enforcement officials said Saturday.
According to an FBI news release, a foreign government said that Tamerlan Tsarnaev appeared to be strong believer and that he had changed drastically since 2010 as he prepared to leave the U.S. for travel to the Russian region to join unspecified underground groups.