Schiff: FBI did 'thorough job' investigating Boston suspect

Schiff, a member of the House Intelligence Committee, suggested that an FBI probe was eventually dropped because investigators did not have enough evidence to pursue suspect Tamerlan Tsarnaev, who along with his brother Dzhokhar, is believed to have carried out the Boston Marathon attack.

"Well it seems like it was two identical or nearly identical inquiries merely sent to two different agencies," Schiff said on CNN's "Starting Point." "The FBI responded, they went out, they interviewed him, they did a background of all the online traffic to find out was there any information indicated he had been radicalized as the Russian inquiry suggested.

"And basically they weren't able to find anything. They did a pretty thorough look based on this single tip," he said.

Since the Boston bombings last Monday, lawmakers have questioned the FBI and CIA's handling of Tamerlan Tsarnaev, asking if agencies did enough to investigate him after Russian authorities raised concerns about his ties to possible Islamist groups.

The FBI spoke to the elder Tsarnaev brother in 2011, but was unaware that he took a six-month trip to a volatile region of Russia in 2012 and did not interview him upon his return.

Reports Thursday said that the CIA had flagged Tamerlan as well and had pushed for him to be placed on a watch list.

But Schiff, a member of the House Intelligence Committee, went on to say there was no indication this was a failure to share information between the CIA and the FBI. The congressman praised the agencies capacity to handle and vet the copious number of tips that came in after the bombings and the reliability of foreign intelligence information.

"They didn't really have a lot to work with," the congressman said, adding that the FBI went back to the Russians multiple times to get more information and were responded to "with nothing but silence."

"We just don't have the capacity to surveil everyone we get a tip on," he said. "Also it's regrettably the fact that some of the foreign intelligence agencies will share misinformation if they want to somehow impugn someone they consider a dissident or undesirable.

"I don't think this was a situation where either agency was withholding something from the other. The reality is the agency that went out and did the investigation wasn't able to find anything. So, I'm not sure what more could have been done,” he added.