(Reuters) - Russian authorities contacted the FBI two years before the Boston Marathon bombings to flag Tamerlan Tsarnaev as a budding terrorist, according to a congressional report read in a U.S. court on Wednesday.
The testimony about the now-dead older brother of convicted marathon bomber Dzhokhar Tsarnaev came as his lawyers sought to spare him the death penalty, arguing he was a pawn in Tamerlan's al Qaeda-inspired scheme to attack the world-famous race.
Russian authorities appealed to the FBI in 2011 to alert them if Tamerlan traveled toRussia, where they said he was angling to join terrorism cells, according to a March 2014 House Committee on Homeland Security report read to jurors in federal court in Boston.
Despite the warning, Tamerlan made a six-month trip to the Russian region of Dagestan in 2012, actively hunting for jihadist opportunities, according to an FBI report of an interview with a relative of the Tsarnaev family, Magomed Kartashov.
Kartashov told investigators that Tamerlan was inspired by radical material he found online and resisted Kartashov's insistence that he reconsider his intentions of joining a violent militant group.
"You have convinced my head, but my heart still wants to do something," Tamerlan was quoted as saying to Kartashov.
Dzhokhar Tsarnaev, a 21-year old ethnic Chechen, was found guilty earlier this month of killing three people and injuring 264 in the April 15, 2013, attack on the race, the worst on U.S. soil since September 2001.
Prosecutors seeking the death penalty for Dzhokhar have painted him as an equal partner with his brother in the bombing, citing al Qaeda propaganda found on his computer and a note he wrote that appeared to cast the attack as retribution for U.S. military campaigns in Muslim lands.
Prosecutors are also demanding that by Thursday the defense call five Tsarnaev relatives brought by the team from Russia to Boston because they are an "enormous expense and distraction" to the FBI, which is protecting them, according to a transcript of a closed-door proceeding obtained by the Boston Globe newspaper.
Martin Richard, 8, Chinese exchange student Lu Lingzi, 23, and restaurant manager Krystle Campbell, 29, died in the 2013 bombing. The Tsarnaev brothers shot dead Massachusetts Institute of Technology police officer Sean Collier three days later.
Richard's parents and Collier's sister have spoken out against the government's pursuit of the death penalty, calling for a deal in which Tsarnaev would be sentenced to life in prison and give up his right to appeal.
(Additional reporting by Richard Valdmanis; Editing by Jeffrey Benkoe)
Scenes from the trial: