The White House briefing room was briefly evacuated Tuesday after a bomb threat was called into police, the Secret Service said.

Secret Service officers interrupted a live, televised press briefing with White House press secretary Josh Earnest and evacuated the James S. Brady Briefing Room shortly after 2 p.m.

Roughly 20 minutes after being evacuated, journalists were allowed back into the White House. Uniformed Secret Service officers on the scene said an all-clear had been issued.

In a statement, Secret Service spokesman Brian Leary said a "telephonic bomb threat concerning the White House Briefing Room was called into the Metropolitan Police Department."

As a precaution, he said, the White House Press Briefing Room was evacuated. The evacuation was limited to the White House Press Briefing Room and did not affect any other sections of the White House.

About 15 minutes after the evacuation, Earnest wrote on Twitter that the briefing would resume shortly after the briefing room was cleared. "Hopefully won't be long," he wrote.

Although parts of the White House have been evacuated before, including after a fence-jumper made it inside the White House last year, this was the first time that an evacuation occurred during a televised press briefing.

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.