WASHINGTON (NewsNation Now) — U.S. Capitol Police are investigating if members of Congress gave unsanctioned tours the day before the breach of the Capitol Complex.

Earlier this week, a letter from over 30 House Democrats called for an investigation from Capitol Police, claiming lawmakers saw “suspicious” tours on Tuesday, Jan. 5, the day before the Capitol was breached by violent pro-Trump supporters as Congress certified the Electoral College vote for President-elect Joe Biden and Vice President-elect Kamala Harris.

House of Representatives Speaker Nancy Pelosi said Friday that any members of the U.S. Congress who helped a crowd of President Donald Trump’s supporters storm the Capitol should face criminal prosecution.

“If in fact it is found that members of Congress were accomplices to this insurrection, if they aided and abetted the crimes, there may have to be actions taken beyond the Congress, in terms of prosecution for that,” Pelosi said.

U.S. House Rep. Mikie Sherrill (D-NJ) first made the accusations Tuesday evening in a public Facebook Live, alleging unidentified colleagues had groups walking around the Capitol in “reconnaissance for the next day.”

Capitol Police confirmed to NewsNation Friday they are investigating the matter.

Wednesday, Sherrill, along with more than 30 other lawmakers, formally requested an investigation from the Acting House Sergeant at Arms, the Acting Senate Sergeant at Arms, and the Acting Chief of the U.S. Capitol Police into what they called “suspicious behavior and access given to visitors to the Capitol Complex” on Tuesday.

According to the letter, first tweeted by Sherrill Wednesday afternoon, she and other lawmakers noticed tours conducted on Tuesday, Jan. 5, that were “a noticeable and concerning departure from the procedures in place as of March 2020 that limited the number of visitors to the Capitol.” The letter continues to say the tours were “so concerning” they were reported to the Sergeant at Arms.

“The visitors encountered by some of the Members of Congress on this letter appeared to be associated with the rally at the White House the following day,” the letter alleges in part, before stating “Given the events of January 6, the ties between these groups inside the Capitol Complex and the attacks on the Capitol need to be investigated.”

Wednesday night, Sherrill said in an interview with MSNBC: “That investigation has started and is ongoing. Make no mistake, the only way these people got access, is if another member got them access or walked them in.”

No Republican lawmakers signed the letter calling for the investigation. That letter did not provide any evidence of the allegations beyond what the lawmakers say they witnessed, but asked a series of questions, including whether authorities track visitors to the Capitol by members of Congress.