Riot shields and gas masks are piled in the hallways and new fencing and other security measures have also gone up around the building that is seen by many as an important global symbol of democracy..
By Tuesday evening, Guardsmen who secure the Capitol were authorized to carry lethal weapons.
National Guard presence at the Capitol has been amped up ahead of the Inauguration as law enforcement braces for a continuation of pro-Trump extremism.
A 2-metre high fence has been erected around the Capitol, with metal barriers and National Guard troops protecting the congressional office buildings that surround it.More news: BREAKING* Hogwarts Legacy: Harry Potter prequel delayed just months after announcement
Increased threats of violence at state capitols across the country have emerged since a mob of violent supporters of President Donald Trump breached the U.S. Capitol on January 6 in an unsuccessful insurrection attempt that resulted in the deaths of five people.
Chelsi Johnson, spokesperson for the DC National Guard, said in a statement to CNN that the move was requested by federal authorities and authorized by Secretary of the Army Ryan McCarthy.
National Guard members sleep, before Democrats begin debating one article of impeachment against US President Donald Trump at the US Capitol, in Washington DC on January 13, 2021.
Cooper, a Democrat, is sending 200 guardsmen to the nation's capital to assist local and civil authorities before and during President-elect Joe Biden's January 20 inauguration.More news: Covid-19 may eventually resemble the common cold in future, scientists predict
The FBI, still hunting those responsible for last week's violence, has issued warnings of possible armed protests and further unrest across the country in the coming days.
The chief of the National Guard Bureau, General Daniel Hokanson, told reporters on Monday that he expected about 10,000 troops in Washington by Saturday to help provide security, logistics and communications.
"There will be no excuse for violence, vandalism or any other form of lawlessness", Rosen said in a video.More news: GM reveals plans to produce flying vehicles