WASHINGTON (AP) — The U.S. Capitol complex temporarily locked down Monday during a rehearsal for President-elect Joe Biden’s inauguration after a fire in a homeless encampment about a mile away sent a plume of smoke into the air and caused security concerns.

But law enforcement officials said there was no threat to the public and the fire was not believed to be a threat to the inauguration. The evacuation of some participants and the lockdown were ordered by the acting chief of Capitol Police in an abundance of caution, officials said. District of Columbia firefighters responded and put out the fire.

Biden was not participating in the rehearsal.

A riot Jan. 6 at the U.S. Capitol by Trump supporters has prompted anxiety and massive security concerns about the inauguration on Wednesday. Secret Service increased security in and around the Capitol a week early in preparation, and the city center is essentially on lockdown with streets blocked, high fencing installed and tens of thousands of National Guard and other law enforcement officers stationed around the area.

Participants were ushered from the West Front of the Capitol. Those who had gathered for a walk-through, including a military band, were directed to head indoors and moved in the direction of a secure location inside the Capitol complex.

People involved in the rehearsal said security officials yelled “this is not a drill.”

The U.S. Secret Service, which is in charge of security for the inauguration, said there was no threat to the public.

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