A man rammed a vehicle into two police officers at a barricade outside the US Capitol in Washington DC on Friday before being shot dead by authorities.

The attack took place close to where armed insurrectionists stormed the complex housing the US Congress on January 6.

What happened in the attack?

Police said a vehicle rammed into two officers protecting the Capitol complex and crashed into a barrier.

They added that the suspect got out of the vehicle and ran towards the officers brandishing a knife.

The driver was then shot by police and died later in hospital.

Both officers were taken to hospital, where one also died.

"It is with a very, very heavy heart that I announce one of our officers has succumbed to injuries," said Yogananda Pittman, acting chief of US Capitol Police. 

The slain officer was identified as William "Billy" Evans, an 18-year veteran of the US Capitol Police force.

"Please keep Officer Evans and his family in your thoughts and prayers," Pittman said in a statement.

Video posted online showed a blue sedan crashed against a vehicle barrier near the complex, and a police K9 inspecting the vehicle.

Were politicians in any danger?

The incident occurred about 100 yards (about 90 meters) from the North entrance of the building on the Senate side of the Capitol, which is typically used by senators and staff on weekdays.

Congress is currently on recess for the Easter holiday.

US President Joe Biden is also not in DC at the moment. Biden said he and First Lady Jill Biden were heartbroken about the attack.

"Jill and I were heartbroken to learn of the violent attack at a security checkpoint on the US Capitol grounds, which killed Officer William Evans of the US Capitol Police, and left a fellow officer fighting for his life," Biden said in a statement.

"We send our heartfelt condolences to Officer Evans' family, and everyone grieving his loss."

Senate Majority Leader Chuck Schumer offered his prayers, while House Speaker Nancy Pelosi ordered flags lowered to half-staff on the Capitol to honor the victim. 

What is known about the attacker?

No information was immediately available on the identity of the attacker or his motivation.

Robert Contee, chief of the DC police department, told a news conference later that there was no longer an ongoing threat.

"It does not appear to be terrorism-related, but obviously we will continue to investigate," he said.

DW's Washington Bureau Chief Ines Pohl said the attack happened just as the city was reopening following the January attack.

"We don't know anything about the suspect, whether he was acting alone, or whether there are more attacks planned, but this city remains on alert, again."

Security remains tight

The US is still reeling from the US Capitol riot, which took place as Congress was voting to certify Biden's presidential win.

Authorities have begun only in the past couple of weeks to remove the outer ring of high, razor-wire-topped fencing erected around the sprawling complex after the attack by thousands of supporters of then-President Donald Trump.

Five people, including a Capitol Police officer, died in the assault inspired by Trump's groundless claims that he had lost the November presidential election due to massive fraud.

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

mm/msh (AFP, AP, Reuters)