FILE - This file photo provided Friday, April 19, 2013 by the Federal Bureau of Investigation shows Boston Marathon bombing suspect Dzhokhar Tsarnaev, charged with using a weapon of mass destruction in the bombings on April 15, 2013 near the finish line of the Boston Marathon. On Thursday, Jan. 30, 2014, U.S. Attorney General Eric Holder authorized the government to seek the death penalty in the case against Tsarnaev. (AP Photo/Federal Bureau of Investigation, File)
FBI Director James Comey testifies on Capitol Hill in Washington, Wednesday, Jan. 29, 2104, before the Senate Intelligence Committee hearing on current and projected national security threats against the US. (AP Photo/Pablo Martinez Monsivais)
This 1982 photo provided by the FBI that appeared on a flier in 1991 shows Dennis Lilly, whose remains have possibly been found in the Gold Bar, Wash., backyard of his wife. He slipped out of a Missouri prison while posing as a guard nearly 30 years ago. (AP Photo/FBI)
An undated photo released by the Federal Bureau of Investigation shows Patricia M. Ferrick, appointed in September 2013 as special agent in charge of the FBI's New Haven, Conn., Division. In an interview with the The Associated Press Wednesday, Jan. 15, 2014, Ferrick said that investigating public corruption is a top priority for her. (AP Photo/Federal Bureau of Investigation)
FILE - In this file photo provided by the Chippewa County, Minn., Sheriff is Buford Rogers who was arrested May 3, 2013, during a raid on a mobile home in Montevideo, Minn. The Minnesota militia member, who faces weapons charges in what the FBI once called a "terror plot" to blow up a police station, is expected to plead guilty, according to a Tuesday, Jan. 7, 2014 update to a federal court calendar. (AP Photo/Chippewa County Sheriff via the Montevideo American-News, File)