Part of the White House was evacuated on Tuesday afternoon because of security concerns related to a bomb threat.

Reporters in the James S. Brady Briefing Room were evacuated onto the North Lawn when secret service agents interrupted White House Press Secretary John Earnest during his daily briefing just after 2 p.m., according to CNN. The bomb threat was phoned in to the Metropolitan Police Department and directly concerned the press briefing room, CNBC reports. As of 2:35 p.m., reporters were allowed back into the White House.

The Associated Press reports that this was the first time an evacuation of a White House room occurred on a live, televised briefing. However, the actual sweep of the room was not televised, according to the AP:

"Many television networks have permanent cameras installed in the briefing room. Journalists from some of those networks said that following the evacuation, the cameras were pointed up to the ceiling such that the briefing room was no longer visible."

CNBC's camera was rolling in the the press briefing room when the evacuation started.

Jonathan Karl, the chief White House correspondent for ABC News, chronicled part of the evacuation on Twitter.