Some lawmakers believe the Boston bombing suspects may have received training to help them carry out their attack.
The FBI says Russian authorities intercepted a phone call between Tamerlan Tsarnaev and his mother Zubeidat Tsarnaeva two years ago that talked about jihad.
"I do think there are persons of interest," Rep. Mike Rogers, R-Mich., said. "In Russia is where I think they went from 'Yes, I'm ready for jihad,' (to) here's how you conduct an act of violence with... including training."
The bombing mastermind's mother says she is not a terrorist and her sons are innocent.
"It's all lies and hypocrisy," she told The Associated Press in Dagestan. "I'm sick and tired of all this nonsense that they make up about me and my children. People know me as a regular person, and I've never been mixed up in any criminal intentions, especially any linked to terrorism."
She and her husband have put off their planned trip to the United States.