Typically, people who blow other people up, don't phone in a warning before hand.

Congressional Hearing Evacuated After Phoned in Bomb Threat Jun 16, 2015, By JOHN PARKINSON, BENJAMIN SIEGEL and ALEXANDER MALLIN
U.S. Capitol building in Washington. Getty Images

   A House Foreign Affairs Committee hearing was briefly interrupted this morning after a bomb threat was called in to a hearing room in the Rayburn House Office Building, authorities said.

U.S. Capitol Police cleared the room after a sweep by a K-9 unit. No hazardous materials were discovered, according to Capitol Police public information officer Lt. Kimberly Schneider.

   When the threat came in, Rep. Ed Royce, R-California, called a 15-minute recess for the hearing, which featured U.S. Ambassador to the United Nations Samantha Power, to allow Capitol Police to investigate, Royce said in a statement.

   "Following an evacuation of the hearing room and adjoining Committee offices, the Capitol Police investigated the situation and determined that it was safe for the hearing to resume," he said.

   Royce commended the police when the hearing resumed. "We appreciate work of the Capitol Police and appreciate their work ensuring the safety of this hearing," he said.

The hearing was evacuated one week after a portion of the Dirksen Senate office building and the White House Press Briefing Room were evacuated after phoned in bomb threats.

   An officer on the scene at Rayburn told ABC News the same caller is suspected, though Capitol Police have not verified the identity of today's caller at this stage of their investigation.