The leading Democrat in the US Senate returned to the floor of Congress and did not mince his words about the pro-Trump demonstrators who violently took control of the US Capitol building on Wednesday. "Those who performed those reprehensible acts cannot be called protesters," said Senate minority leader Chuck Schumer, who is likely to be the majority leader after Joe Biden is sworn in as president on January 20. "No, there were rioters and insurrectionists, goons and thugs," he said, referring to the protesters who some say were encouraged by incumbent President Donald Trump. "They were a few thousand violent extremists who tried to take over the Capitol building and attack our democracy. They must be prosecuted to the fullest extent of the law." Mr Schumer told those on the congressional floor that contrary to what some in the Trump camp might claimg, he felt the president was responsible for Wednesday's violence. "Today's events certainly would not have happened without him. This violence, in good part, his responsibility, will be his everlasting shame," said Mr Schumer. Mr Schumer, a longtime senator from New York state, has been one of the most consistent critics of Mr Trump during his four-year term. Mr Schumer, who many consider to be part of a more progressive wing of the Democratic Party, makes regular visits to every New York county and is a staple on network and cable TV shows throughout the US. The protests on Wednesday were an effort to try to stop the vote certification process that confirmed Mr Biden's victory in the race to the White House last November. Thousands appeared in Washington on Wednesday at a rally at which Mr Trump spoke. The protests turned violent in the evening with some of the demonstrators overwhelming Capitol police and disrupting congressional work. In a video posted on Twitter and Facebook, Mr Trump encouraged supporters to stem the violence, while also repeating his unproven claims of election fraud, which many say encouraged much of the violence to begin with. As a result of several tweets and the video, both Twitter and Facebook locked Mr Trump's accounts. It remains to be seen when he will be able to use them again. Some rioters entered congressional offices on Capitol Hill, threw papers around and left behind threatening messages. They also posed for photos holding Trump flags and various documents from inside offices. One woman was fatally shot inside the building by a Capitol police officer. Three others died outside as a result of various medical incidents, police said. "I want to thank many of the Capitol Police and Secret Service and local police who kept us safe today," said Mr Schumer. "It is very, very difficult to put into words what has transpired today. I have never lived through or even imagined an experience like the one we have just witnessed in this capital."