Washington DC - A South Florida member of the far-right Proud Boys was sentenced to five years in prison Wednesday after federal prosecutors described him as "one of the most violent January 6 rioters" who assaulted at least six police officers while attacking the US Capitol three years ago.

Kenneth Bonawitz (58) grabbed one of the officers in a choke hold and lifted her up and injured another so badly that he was forced to retire, according to federal prosecutors.

Bonawitz, a member of the Miami chapter of the Proud Boys, was carrying an 8-inch knife in a sheath on his hip when he stormed the Capitol with a mob of Donald Trump supporters after gathering for the president's "Stop the Steal" rally on the Ellipse before the attack.

"Police seized the knife from him in between his barrage of attacks on officers," Assistant US Attorney Sean McCauley wrote in a sentencing memo recommending the high end of the guidelines, or nearly six years in prison.

"His violent, and repeated, assaults on multiple officers are among the worst attacks that occurred that day."

US District Judge Jia Cobb in Washington DC gave Bonawitz a five-year sentence, followed by three years of supervised release.

Arrested a year ago, he pleaded guilty in August to three felonies – one count of civil disorder and two counts of assaulting police.

Last week, a man who also belonged to the same local Proud Boys chapter was sentenced to four years in prison for participating in the insurrection on January 6, 2021, at the US Capitol, which aimed to block the congressional certification of the presidential election won by Joe Biden.

A Washington, DC, federal judge found 49-year-old Gilbert Fonticoba guilty of civil disorder and obstruction of an official proceeding in October.