The US President-Elect described the scenes as 'one of the darkest days in the history of our nation'

US President-Elect Joe Biden said there was no question that Black Lives Matter protesters would have been treated differently to the "mob of thugs" who stormed the US Capitol.

Pounding the podium, Mr Biden said the double standard was "totally unacceptable".

He said his granddaughter had raised the discrepancy of the treatment of crowds of Donald Trump supporters, who attempted to use force to halt his confirmation by Congress.

The extraordinary scenes of violence, which led to four deaths, were greeted with horror around the world.

Mr Biden said: "No one can tell me if it had been a group of Black Lives Matter protesting yesterday, they wouldn't have been treated very, very differently than the mob of thugs who stormed the Capitol.

"We all know that's true and it is unacceptable. Totally unacceptable."

Black Lives Matter protests over the summer were met with a heavy law enforcement response, including the presence of the national guard.

Critics have pointed to the discrepancy between the response to the protests and the crowds of Trump supporters, who were able to lay siege to the Capitol buildings where they clashed with police.

Speaking in Delaware on Thursday, Mr Biden described the events as "one of the darkest days in the history of our nation" and "an unprecedented assault on our democracy".

He said: "What we witnessed yesterday was not dissent, it was not disorder, it was not protest, it was chaos," he said.

"They were a riotous mob, insurrectionists, domestic terrorists."

Biden blamed his predecessor for unleashing "an all out assault on the institutions of our democracy" and said the events in Washington were the culmination of Mr Trump's efforts.

He said Mr Trump had "incited a mob" to mount an attack on the Capitol in an attempt to thwart the will of the US people.

"Our president is not above the law," he said.

His comments came after he was officially confirmed as the 46th US president on Thursday, after lawmakers were able to return to the Capitol under armed guard.

Meanwhile, Facebook blocked Mr Trump "indefinitely and for at least the next two weeks" following the rioting in Washington.

The social network's boss Mark Zuckerberg warned that Mr Trump planned to use his remaining days in office "to undermine the peaceful and lawful transition of power to his elected successor, Joe Biden".

Transportation Secretary Elaine Chao became the first Cabinet Secretary to abandon Mr Trump, resigning in protest at the scenes of violence.Ms Chao, the wife of Republican Senate Leader Mitch McConnell, said the Capitol attack "has deeply troubled me in a way that I simply cannot set aside."

House Speaker Nancy Pelosi called for Mr Trump's immediate removal from office through the 25th Amendment of the US Constitution.

"Yesterday, the President of the United States incited an armed insurrection against America," she told reporters and accused him of committing a "seditious act".

The 25th Amendment allows a President to be removed from office if they cannot complete their duties.

Mr Trump has two weeks left to serve until Mr Biden is inaugurated.