WASHINGTON -- Several floors of a Senate office building were evacuated -- including an oversight hearing reviewing the Transportation Security Administration (TSA), which has come under scrutiny for their inability to find bombs during security inspections -- after a bomb threat was phoned in to police. Capitol Police cleared most of the Dirksen Senate Office Building, which is across the street from the Capitol and houses Senators' offices as well as committee hearing rooms.

A few hours later, the White House press briefing room was evacuated by Secret Service and bomb sniffing dogs were brought into the room, AFP reported. Reporters were allowed to return shortly after. President Barack Obama was in the White House at the time.

Capitol police received a “phoned-in bomb threat” about a “suspicious package” in room 340 of Dirksen, which is next to the room where the TSA hearing was taking place, according to a spokeswoman for the agency.

About an hour later, the building was cleared and staff were allowed to return inside. The police determined a second report of a “suspicious package” was an unattended lunch cooler left in another building’s courtyard, CQ reported.

The Capitol building was allowed to continue functioning as normal, with tours resuming. Members of the Senate had returned to work in the complex Tuesday morning, but House members were still headed back into town from the weekend.

Police inspected the office building with bomb-sniffing dogs, forcing crowds of staffers to remain on the sidewalks outside the building. Police also searched the Capitol building.

The bomb threat appeared to coincide with a hearing that the Senate Homeland Security Committee was conducting to discuss the TSA, the agency tasked with keep the nation’s airports safe. The agency has come under scrutiny recently for failing to adequately detect the presence of bombs entering the nation’s airports.

During testimony, Robert MacLean, a federal air marshal from Los Angeles, and Sen. Ron Johnson, R-WI, interrupted to announce that Capitol Police were clearing the room. “In an orderly fashion, please exit as quickly as possible,” Johnson said. (Video available at link.)

The security of the Capitol came under more intense scrutiny in recent months after several high profile incidents. In April, a man walked up the steps of the west front of the building and shot himself. Less than a week later, another man flew a small gyrocopter onto the lawn of the Capitol in protest of campaign finance laws. His flight raised concerns that someone with more malicious intents might have been able to fly into the building. Then in May, an intern for a member of the House carried an unloaded gun into the Rayburn House Office Building and was able to reach the elevators before being stopped by police.