One officer killed and another injured in another US Capitol attack

One officer was killed and a second injured Friday after a vehicle rammed through security and crashed into a barrier at the US Capitol, forcing it into lockdown less than three months after a mob assault on Congress.

Capitol Police shot dead the driver after he jumped out of the car and lunged at them with a knife, Acting Chief Yogananda Pittman told reporters.

No information was available on the identity of the attacker or his motivation, but Washington Metropolitan Police Chief Robert Contee indicated that a terror link was not suspected at this stage.

“It does not appear to be terrorism-related, but obviously we will continue to investigate,” said Contee.

National Guard troops were mobilized and staff at the huge Capitol complex ordered to stay away from windows and seek cover after alerts went out over the incident.

Television footage showed a blue sedan crashed into a security barrier on one of the streets leading to Congress, as what appeared to be the injured officers were loaded onto gurneys and into ambulances.

A helicopter landed on the Capitol grounds and the police were loaded on board to be taken to a hospital.

The attack came amid tightened security in Washington after the January 6 insurrection by supporters of then-president Donald Trump.

In that attack, hundreds smashed into the Capitol building yelling threats against politicians and shutting down the legislature.

One Capitol Police officer died as a result of the attack, as well as four others individuals who took part or were nearby.

Since then security officials have said there is an ongoing threat from extreme-right groups and Trump supporters.

More than 300 people have been charged in the January attack, including members of armed extremist groups like the Proud Boys and Oath Keepers, and 100 more are expected to be charged, according to Justice Department court filings.

In recent weeks some security has been loosened, with the number of armed National Guard troops at the Capitol reduced and a security fence that created a broad perimeter around the Capitol complex removed.

CBS News reported that security officials had already warned congressional staffers of a threat before the car ramming.

Text messages sent to staffers inside told them to avoid windows and said no one could enter or leave the building.

“If you are outside, seek cover,” the messages said.

But the danger on Friday was limited as Congress was in recess for the Easter holiday and relatively few people were in the building.

Security officials, including the Capitol Police and National Guard, were faulted for reacting slowly to the crowds who stormed the Capitol on January 6.

Several hundred rioters broke down doors and windows and poured into the halls of the legislature, some calling for physical attacks on members of Congress and on then-vice president Mike Pence, who was there to preside over a session to formally declare Joe Biden the winner of the election.

While the incident remains under investigation, some have alleged that Trump and supporters encouraged the attack and that Trump officials held back on deploying additional law enforcement and troops to fight back the attackers.

Since then several thousand National Guardsmen and women have remained deployed to the US capital city due to ongoing security concerns. (AFP)