The angle of the footage shows the assault happening beneath a “Blue Lives Matter” flag, which purports to show solidarity with law enforcement officers killed in the line of duty and depicts a black and white Stars and Stripes with a thin blue line across the centre.
It has been criticised for having been coopted by extremists and used as a symbol of white supremacy, notably in Charlottesville in 2017.
Such flags are often seen at Trump rallies and several were evident during the attack on the US Capitol as officers were beaten, tasered, and crushed by the surging crowd.
In the video, rioters can be heard shouting “They have an MPD” meaning an officer of the Metropolitan Police Department.
Shouts of “Get his ass” can also be heard.
At one point during the assault on him, Officer Fanone was electroshocked with a taser by Trump-loyalist rioter Danny Rodriguez, who has since confessed to his actions.
Officer Fanone suffered a heart attack and other injuries that could have also proved fatal during the attack. He later testified about his experience that day before Congress.
Capitol Police officer Harry Dunn, who is Black, said in February that pro-Trump rioters shouted racial slurs at him and beat other officers with Blue Lives Matter flags.
He told ABC News that he remembered telling another officer on 6 January: “I got called a [N-word] a couple dozen times today protecting this building. Is this America? They beat police officers with Blue Lives Matter flags. They fought us, they had Confederate flags in the US Capitol.”
The new footage will air on Wednesday night in a documentary on HBO, Four Hours at the Capitol.
The programme examines the events of the storming of the Capitol, which left five people dead and injured almost 140 police officers.
Four subsequent suicides of law enforcement personnel have also been linked to that day.
The HBO documentary was directed by Jamie Roberts and produced by Dan Reed in association with the BBC.
Register for free to continue reading
Registration is a free and easy way to support our truly independent journalism
By registering, you will also enjoy limited access to Premium articles, exclusive newsletters, commenting, and virtual events with our leading journalists
Already have an account? sign in