Tsarnaev's parents have denied their son was involved with any militant or extremist groups, insisting Tamerlan and Dzhokhar are being framed by the U.S. government.
In late 2011, the CIA requested that Tamerlan Tsarnaev and his mother be placed in a U.S. terrorism database after it received information from the Russian government that the pair could be potential Islamic militants. By that time the FBI had already looked into Tamerlan and determined he did not have ties to terrorism. U.S. officials recently learned that Russian forces had wiretapped conversations between Tamerlan and his mother.
America's Director of National Intelligence, James Clapper, has called for an intelligence community review of how information on Tamerlan was handled prior to the Boston attack – a move President Obama said today was "standard procedure around here."
"We want to leave no stone unturned," Obama said.
Overnight new video emerged from a boxing documentary that featured Tamerlan Tsarnaev from his days as a fighter trying to make the U.S. Olympic team.
In a short clip of the 2010 video, obtained by Entertainment Tonight, Tamerlan is seen wearing his boxing gear and says his name while smiling broadly for the camera.
ABC News' Megan Chuchmach and Luis Martinez contributed to this report.