The United States House of Representatives’ Select Committee investigating the January sixth attack on the Capitol in Washington DC has begun hearing testimony into the genesis of the insurrection by former president Donald Trump’s supporters.

The session has been hearing testimony from four police officers about the physical, verbal and emotional assaults they endured when hundreds of Trump supporters stormed the Capitol precinct where Congress was in session certifying the election victory of president Joe Biden.

The four officers’ testimony followed powerful opening statements from committee chair, Bennie Thompson, who repudiated those mainly from the Republican Party that seek to diminish the severity of the January 6 assault, one he said was based on a vile lie that the election had been stolen.

Liz Cheney, one of just two GOP members serving on the committee against the wishes of her party, said that if those responsible were not held accountable and if Congress did not act responsibly then the events of January 6 would remain a cancer on the constitutional republic.

The committee also saw new video of the assault as it unfolded in gut-wrenching fashion as rioters hunted members of Congress, including speaker Nancy Pelosi.

The committee’s work is expected to last a number of months.

Trump supporters march to the US Capitol: