In a little-noticed exchange before the House Judiciary Committee Thursday, Mueller acknowledged that the Russian alert was not the first time the elder Tsarnaev brother crossed the FBI’s radar.

“His name had come up in two other cases,” Mueller said in response to questions from Rep. Steve King (R-Iowa). “Those two other cases, the individuals had their cases closed. So, he was one or two person [sic] away.”

When King asked Mueller if it was reasonable to say that the Russian letter “refocused”  the FBI on Tsarnaev, Mueller replied, “Absolutely.”

Mueller did not elaborate on the nature of the prior investigations where Tsarnaev’s name had arisen. However, an FBI official told POLITICO they were not related to terrorism. The official, who asked not to be named, also said the agent who conducted an “assessment” of Tsarnaev in response to the Russian warning in 2011 found the previous references and was aware of them.