US media say the suspect in Friday's deadly attack outside the Capitol in Washington is a 25-year-old man.
Police say the suspect rammed his car into two Capitol police officers at a security checkpoint on Friday, killing one and injuring the other. He got out of the car wielding a knife, but police shot him dead.
Media reports say the man posted on social media about losing his job. But his motive for the attack remains unknown.
Fortification of the Capitol was strengthened following the January 6 riot, but was recently eased. Sections of surrounding roads have reopened for traffic.
President Joe Biden issued a statement expressing condolences over the death of the police officer. He ordered flags at the White House to be lowered to half-staff.