Lawmaker: FBI Checking Training Angle In Marathon Bombings

The chairman of the House Homeland Security Committee said Sunday that the FBI is investigating in the United States and overseas to determine whether the suspects in the Boston Marathon bombing received training that helped them carry out the attack.

Dzhokhar Tsarnaev, 19, is charged with joining with his older brother, Tamerlan, who's now dead, in setting off the shrapnel-packed pressure-cooker bombs. The bombs were triggered by a remote detonator of the kind used in remote-control toys, U.S. officials have said.

U.S. officials investigating the bombings have told The Associated Press that so far there is no evidence to date of a wider plot, including training, direction or funding for the attacks.

A criminal complaint outlining federal charges against Dzhokhar Tsarnaev described him as holding a cellphone in his hand minutes before the first explosion.

The brothers are ethnic Chechens from Russia who came to the United States about a decade ago with their parents.

"I think given the level of sophistication of this device, the fact that the pressure cooker is a signature device that goes back to Pakistan, Afghanistan, leads me to believe — and the way they handled these devices and the tradecraft — ... that there was a trainer and the question is where is that trainer or trainers," said Rep. Michael McCaul, R-Texas, on "Fox News Sunday."

"Are they overseas in the Chechen region or are they in the United States?" McCaul said. "In my conversations with the FBI, that's the big question. They've casted a wide net both overseas and in the United States to find out where this person is. But I think the experts all agree that there is someone who did train these two individuals."

Rep. Adam Schiff, D-Calif., a member of the House Intelligence Committee, said he thought it's "probably true" that the attack was not linked to a major group. But, he told CNN's "State of the Union," that there "may have been radicalizing influences" in the U.S. or abroad. "It does look like a lot of radicalization was self-radicalization online, but we don't know the full answers yet."

On ABC's "This Week," moderator George Stephanopoulos raised the question to the chairman of the House Intelligence Committee about FBI suspicions that the brothers had help in getting the bombs together.