Updated

A senior Russian official says the Boston Marathon bombings could have been prevented if American officials had followed through with Russian intelligence.

Officials previously hewed to President Vladimir Putin's statement that Russia had no information that could have prevented the attacks.

"The Russian side warned the American side about the Tsarnaev brothers, but this information was not taken seriously by the American side, which is what led to that tragedy," Valentina Matvienko, the speaker of Russia's senate, said Tuesday, referring to suspects Tamerlan and Dzhokhar Tsarnaev, the Interfax news agency reported.

Russia told the FBI in 2011 that Tamerlan Tsarnaev had plans to join insurgents in Chechnya. The agency did a cursory investigation and closed its assessment on Tsarnaev.