Capitol Security Police said on Wednesday they were ready to respond to "all threats" by alerting to the "possible plan of a militia" to attack the seat of the US Congress on Thursday, the target of a deadly assault by pro-Trump protesters on January 6.
Dozens of agents deployed, police on the lookout.
Security was tightened in the US Congress after the alert on a "possible plan of a militia" to attack the Capitol on Thursday.
A threat taken very seriously on the spot two months after the deadly assault given by pro-Trump protesters in early January.
Members of the QAnon conspiracy movement, who have never accepted Joe Biden's victory, believe that March 4 will see Donald Trump invested as president of the United States for a second term.
Until 1933, presidents were sworn in on that day.
Votes postponed to keep parliamentarians away
As that date approaches, police are closely monitoring calls to rally pro-Trump protesters in a country still reeling from the January 6 attack.
"We have obtained information which shows a possible plan of an identified militia to force the entry of the Capitol on March 4", detailed the police, affirming to be "prepared for any potential threats".
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After the alert given by the police, the House of Representatives advanced to Wednesday evening two votes scheduled for Thursday, which will allow its some 430 parliamentarians not to return to the hemicycle before next week.
Several of them had testified to the trauma experienced in early January when they had to hide from the insurgents.
"Significant reinforcement of security"
The police stressed that they "have already made a significant increase in the security" of the Capitol since the January coup.
Members of the National Guard still patrol the compound, protected by barriers and barbed wire.
Security is at the heart of the debates this week in the Senate, with hearings of several officials to better understand the loopholes that led to the failure of January 6.
Tuesday in front of the senators, the boss of the FBI had also compared the American domestic terrorism to a metastasis which is not ready to disappear.