Capitol Hill

The man, identified as Floyd Ray Roseberry, 49, surrendered hours after the threat was made.

US Capitol Police had been negotiating with the driver who had parked a pick-up truck near the Library of Congress, across the street from the Capitol building and Supreme Court.

His motives remain unknown. Police are still searching the vehicle.

Congress is currently in recess, but some staff are working in the Capitol. Several office buildings were evacuated.

"The department prepared in order to meet these challenges, but we did not do enough," said Yogananda Pittman, who took over when the ex-chief resigned.

Despite "strong potential for violence" the force did not adequately prepare for a "terrorist attack," she said.

Five people, including a Capitol Police officer, died in the riot.

Chief Pittman was speaking on Tuesday to the House Appropriations Committee, which oversees the police department's funding.

Police say they acted out of an abundance of caution after witnesses reported smoke rising nearby. The fire was several blocks away.

A rehearsal for Mr Biden's inauguration was suspended.

Security is tight, with thousands of National Guard members deployed at the Capitol and around central Washington DC, after five people died on 6 January when a pro-Trump mob stormed the Capitol, home to the US Congress.

An alert circulated earlier to Capitol staff said the complex was on lockdown, with no-one being allowed in or out.

More than a dozen states have activated National Guard troops to help secure their capitol buildings following an FBI warning of armed demonstrations, with right-wing extremists emboldened by the deadly attack on the US Capitol in Washington on January 6.

Security officials had eyed Sunday as the first major flashpoint, as that is when the anti-government "boogaloo" movement made plans weeks ago to hold rallies in all 50 states.

Capitals in battleground states, where Trump has directed his accusations of voter fraud, were on especially high alert.

Footage of the officer, identified as Eugene Goodman, shows him just steps ahead of rioters as they chase him up a flight of stairs.

Mr Goodman is then seen glancing toward the Senate entrance before luring the men in the opposite direction.

Five people, including a police officer, died as a result of the riots.

Another officer who was on duty during the siege died by suicide this weekend, his family said.

Some were seen taking pictures of the monuments and taking a break on the steps that were occupied by rioters last week.

Another 10,000 will arrive on Saturday as the FBI warns of the risk of more violence from armed extremists holding pro-Trump events in 50 state capitols between now and inauguration next week.

Washington DC Mayor Muriel Bowser is urging people to avoid coming to the city for Joe Biden's presidential inauguration on 20 January.

She says people should participate virtually instead.

Pro-Trump extremists entered the premises armed with shields and rioting equipment.

They destroyed parts of the historic building, defaced property and invaded the senate floor, disrupting Congress who had to be evacuated to safety.

In a Twitter statement, Michelle Obama wrote about her hurt and frustration witnessing the riot and the contrast between Black lives matter protests and the invasion of the Capitol building.

"It all left me with so many questions - questions about the future, questions about security, extremism, propaganda and more," she said.

After closed-door meetings on Capitol Hill Wednesday, Kerry said President Barack Obama has made it clear that the U.S. wants to take a leadership role on humanitarian issues.

"We are looking hard at the number that we can specifically manage with respect to the crisis in Syria and Europe," he said. "That's being vetted fully right now."