The second US Capitol Police officer struck during an attack in Washington DC is in stable condition

Another officer, William Evans, died after a man rammed his car into a barrier and got out wielding a knife.

The offender, Noah Green, was shot dead by police.

He posted on social media in the weeks before the attack that he'd lost his job and suffered medical problems.

Green also believed the federal government was targeting him with mind control.

U.S. Capitol Police don't believe the attack was terror-related.