GOP Rep. Michael McCaul said Trump should tell his supporters to "stand down."
Security officials have said Trump supporters could try to breach the Capitol on Thursday.
"This threat is credible, it's real," McCaul said.
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Former President Donald Trump should tell his supporters to "stand down" after security officials said they'd found evidence of a plot targeting the US Capitol in Washington, DC, this week, a senior House Republican said.
"I think President Trump has a responsibility to tell them to stand down," Rep. Michael McCaul, the ranking Republican on the House Foreign Affairs Committee, told CNN on Wednesday.
"This threat is credible, it's real," he said.
The Capitol Police said on Wednesday that it had intelligence about a "possible plot" by a right-wing militant group to breach the Capitol on Thursday.
House Majority Leader Steny Hoyer said the chamber would wrap up its business on Wednesday, a day earlier than planned.
Timothy Blodgett, the acting House sergeant at arms, told representatives in a memo this week that the police were monitoring "information related to March 4th and potential protests and demonstration activity surrounding what some have described as the 'true Inauguration Day.'"
Less than two months ago, on January 6, hundreds of Trump supporters breached the Capitol. The insurrection left five people dead, including one Capitol Police officer.
Blodgett said in the memo that Capitol Police on Tuesday "received new and concerning information and intelligence indicating additional interest in the Capitol for the dates of March 4th-March 6th by a militia group."
The Department of Homeland Security and the FBI also issued an internal intelligence memo about "extremists discussing March 4 and March 6," CNN reported.
The threat appears to be linked to a baseless conspiracy theory, promoted online by far-right groups, that Trump will formally rise to power again on March 4, The Associated Press reported.
Extremist groups including the Three Percenters and supporters of the QAnon conspiracy theory have suggested Trump will reclaim his presidency that day and purge his opponents, Insider's Erin Snodgrass reported.
The theory is based on the fact that the inauguration date for US presidents and vice presidents was March 4 until 1933, when it was moved to January 20.
The Capitol Police significantly increased security around the building after the insurrection on January 6. Hundreds of National Guard troops remained stationed around the area, and fencing was erected.
Blodgett said in his memo that the National Guard would continue to station troops around the Capitol to help the Capitol Police with "maintaining an increased security posture."
It remains unclear whether far-right groups are actually planning to travel to Washington this week or whether the discussions are only online chatter.