WASHINGTON — President Joe Biden has heavily criticized former President Donald Trump on the first anniversary of the attack on the US Capitol, BBC reported.

In a televised speech Biden accused his predecessor of spreading "a web of lies" that led to the mob's assault.

Trump supporters stormed the Capitol building on 6 January 2021 as Congress gathered to certify Biden's presidential election victory.

Live footage of US politicians cowering from the mob shocked the world.

Trump had urged protesters at a rally outside the White House shortly beforehand to "peacefully" march on Congress, but he also encouraged them to "fight" and stirred up the crowd with unsubstantiated claims of mass voter fraud in the election he had just lost.

Shortly after Biden's speech on Thursday Trump released an angry statement hitting out at his successor. In it, he accused Biden of "failure" and repeated false claims about the election.

Democrat politicians, who have a majority in the US Congress, planned a number of events to mark the one-year anniversary of the attack - including a candlelit vigil outside the Capitol building.

Many spoke about their experiences of the day, including sheltering and hiding from the rioters along with young members of staff.

A House committee is conducting an inquiry, and so far investigators have arrested 725 suspects in connection with the riot.

Biden condemned the attackers and Mr Trump in his speech on Thursday, using some of his strongest language yet about both the Capitol riots and his predecessor.

"Those who stormed this Capitol and those who instigated this incidence, held a dagger at the throat of America and American democracy", Biden said in Statuary Hall, a section of the Capitol complex that was breached by rioters.

"They came here in rage, not in the service of America, but rather, in the service of one man.

"The former president of the United States of America has created and spread a web of lies about the 2020 election... His bruised ego matters more to him than our democracy or our constitution".

The US leader also warned that the threats to American democracy "have not abated."

Later in the day House Speaker Nancy Pelosi presided over a moment of silence on the chamber floor. She praised police officers who defended lawmakers and other people who were sheltered inside as the riot raged.

"The insurrectionists targeted more than just the building. They targeted democracy itself," she said.

Some Republicans skipped the day's commemorative gatherings. The party's Senate leader, Mitch McConnell, led a delegation to the funeral of a former senator in Atlanta, Georgia.

Meanwhile Florida congressman Matt Gaetz and Georgia congresswoman Marjorie Taylor Greene - two provocative pro-Trump members of the House - held a news conference at the Capitol billed as a "Republican response" to the day's events.

They repeated unsubstantiated theories that the attack was fuelled by federal agents.

The mother of Ashli Babblit, a US Air Force veteran who died after being shot by police while trying to storm the House of Representatives, also spoke outside Congress.

"She was a patriot. She served this country her whole adult life," Micki Witthoeft told the Alabama-based Right Side Broadcasting Network.

Republican Senator Lindsey Graham, in a tweet, accused Biden of "brazen politicization" of the 6 January riot.