Trump's eldest son,Donald Trump jnr,warmed up the crowd by warning of challenges to Republican members of Congress who didn't back the pro-Trump efforts."We're coming for you,"he said.

In urging his supporters to see the routine act of certifying the US election results as an illegal affront against him and against them,the President helped set in motion hours of violence and chaos that continued as darkness fell on Wednesday evening.

"There's no question the President formed the mob,"Liz Cheney,a Republican from Wyoming,told Fox News."The President incited the mob. The President addressed the mob. He lit the flame."

People carrying Trump campaign flags — some of them appearing to be armed — swarmed the Capitol complex. They broke into the building and draped a Trump flag over the Capitol balcony,disrupted the process of the vote certification and forcing members of Congress,journalists and other officials to take cover or flee the building. Shots could be heard at one point. Pence was whisked to a secure location,as were other legislators.

Trump monitored the scene as it unfolded on television,according to administration officials and people close to the White House. He holed up in the Oval Office,speaking to Mark Meadows,the White House chief of staff,who was said to have been rattled by the day,and Pat Cipollone,the White House counsel.

Trump jnr posted a tweet urging supporters to stop the violence. Ivanka Trump,a White House adviser,denounced the violence and corrected an initial tweet in which her reference to"patriots"made her intention unclear. There was silence from the first lady,Melania Trump,and the President's son Eric tweeted about how many people sang to him for his birthday at the rally.

Two of the President's former chiefs of staff criticised the mob. His former counsellor,Kellyanne Conway,said on ABC News that the mob was made up of"extremists". His former communications director Alyssa Farah urged him publicly to say something.

But the President resisted repeated requests from advisers,some made directly to him,others to Meadows and other aides.

Trump initially rebuffed requests to mobilise the National Guard,according to a person with knowledge of the events. It required intervention from Cipollone,among other officials,according to the person. About 1750 National Guard troops from the District of Columbia and Virginia were to deploy on Wednesday night,a National Guard spokesman said.

As allies of the President began to go public with their disgust about what was taking place at the Capitol and urged him to speak out,White House aides finally coaxed Trump into a tweet in which he did not condemn the violence.

Then they convinced him he needed to say something in a video statement,which Trump opened with another declaration that the election was"stolen"from him and his supporters,before he said"go home",ending with words to the supporters:"I love you."Facebook removed that video,and Twitter later did as well.

Then he made clear that he viewed the day as an expression of his grievances."These are the things and events that happen when a sacred landslide election victory is so unceremoniously&viciously stripped away from great patriots who have been badly&unfairly treated for so long,"he wrote on Twitter."Go home with love&in peace. Remember this day forever!"

That tweet was also removed by Twitter,whose officials announced about 7pm that they were locking his account for 12 hours.

One Trump ally,Senator Rand Paul of Kentucky,predicted as Congress prepared to reconvene on Wednesday night that there would be no further objections from senators to the certification. But Trump told advisers he wanted to see the senators keep going on with the fight.

Several White House advisers described themselves as alternately disgusted,scared or shocked by what had taken place. And the work of government continued on around Trump,seemingly without his participation.

The Defence Secretary and the chairman of the Joint Chiefs of Staff conferred with Pence,not Trump,about sending support to reel in the riots. The national security adviser,Robert O'Brien,condemned the"mob"and praised Pence.

Several Democrats,meanwhile,called for Trump's impeachment. Others — including some Trump administration officials — privately speculated about whether the 25th amendment would be invoked to remove him from office with just two weeks left in his term.

The New York Times