WASHINGTON – U.S. Capitol Police evacuated an office building late this afternoon after a prankster pulled a fire alarm, marking the third such evacuation in less than two months, WorldNetDaily has learned.

Emergency alarms went off in the House Cannon Office Building at about 3:55 p.m.

Police herded staffers outside as special counterterror units armed with MP-5 submachine guns fanned out around the perimeter of the building.

At least one ambulance was called to the scene and ordered to remain “on stand-by,” a paramedic told WorldNetDaily.

Several staffers, citing two earlier false alarms, were in no rush to leave the building and stand out in the cold.

The building had been cleared around Halloween after a
security x-ray monitor showed what looked to be a gun
in a staffer’s bag. It was just a water pistol.

More recently, Cannon was evacuated again when police detected a “funny smell” in the building, a staffer recalled. Police worried about a chemical attack, but the source of the smell turned out to be paint thinner.

This time, police learned a prankster had triggered the alarm and allowed staffers back into the building not long after the evacuation.

“Someone pulled a fire alarm,” said a Capitol Police spokesman. He said they had no suspects.

As sirens blared and emergency lights flashed in the halls during the evacuation, no emergency procedures announcement was broadcast on the PA systems set up in lawmakers’ offices after 9-11. Instead, police went up and down halls evacuating offices.

Congress is out of session for the holidays, and most lawmakers are back home and won’t be back in office until Jan. 20.

The Capitol was the intended target of the fourth plane on 9-11.

The terror threat level remains at “elevated,” or yellow, the midpoint on a five-point scale.

The Department of Homeland Security has asked the public only to remain “vigilant” over the holidays, but has privately ordered law enforcement to beef up protective measures in case of attack.

According to a five-page DHS security directive, the department has picked up increased al-Qaida terrorist chatter and has “recent information” about threats, although it has no specifics about the timing or location of planned attacks.

As WorldNetDaily first reported, the internal DHS memo warns of attacks on chemical plants by air cargo and passenger planes or car bombs. It also warns of terrorist attacks on subways and other crowded indoor facilities using an improvised device to spread cyanide gas through ventilation systems, as WorldNetDaily also first reported.

Cyanide gas, which emits a bitter almond odor, can quickly asphyxiate victims.

Previous stories:

Homeland Security: Al-Qaida could gas subways

Feds to cops: Prepare for car bombs

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