New Delhi, Jan 7 (IANS): The Congress party on Thursday expressed concern over chaos in the US capital Washington D.C., where a woman was killed after outgoing American President Donald Trump's supporters stormed the Capitol building, disrupting the functioning of the US Congress while it was in the middle of ratifying Joe Biden's election as President.

"Scenes from the US are deeply disturbing. Democracy and freedom are the essence of America's greatness. The entire world is watching. May the people of America preserve the dignity of their nation and let the democratic process prevail peacefully," Congress General Secretary Priyanka Gandhi Vadra said.

On Wednesday, Trump-backers stormed the Capitol that houses Congress, TV broadcasts showed what appeared to be flash bombs going off and smoke, which may be from teargas, coming out of a part of the building and some of the mob leaving the area jumping out of a window.

Congress leader and former Union Minister Manish Tewari said: "If peaceful transfer of power can be interrupted in Washington DC, what is the signal being sent out to other right wing bigots around the world... Mobocracy is Kosher if you lose democratically... very unfortunate... in what happened in USA lies a message."

The riot started when the US Congress was holding a joint session to ratify the electoral college votes electing Democrats Joe Biden as President and Kamala Harris as Vice President.

Thousands of the rioters shouting "Trump" and "USA, USA" overwhelmed the police and pushed the barriers around the Capitol and rushed after the joint session adjourned for the Senate and the House of Representatives met separately to consider objections to the electoral college votes from Arizona.

The rioters reached all the way into the Senate chamber, from where the Vice President was hustled away by the security personnel.

A rioter was seen on tweets sitting in the chair of the Senate president and on TV people with Trump flags and placards were shown wandering around the chamber.