Disturbing footage from the US Capitol riot shows the moment a police officer was viciously attacked by an angry right-wing mob, according to a report Sunday.

Ruthless rioters were caught on camera as they stormed the building entrance Wednesday and dragged a cop down a staircase before trampling him and pelting him with objects, according to storyful.com.

The cop was left face-down on the ground during the chaotic scrum as violent protesters chucked a leg crutch and water bottles at him, according to the news agency.

At one point, a man appears to try to strike the officer with a long stick, near a line of police officers guarding the entrance of the building — but it’s unclear if he succeeds.

“USA! USA!” the rioters, some waving Trump flags, can be heard chanting.

The cop — who was sporting tactical gear, including a helmet — suffered blows to the head from members of the wild mob, the agency reported.

On Thursday, Capitol Police Officer Brian Sicknick died from injuries he suffered while fighting off rioters. Four others died during the violent siege.

The name of the beaten officer wasn’t immediately clear Sunday.