Secret Service text messages from around the time of the attack on the U.S. Capitol were deleted despite requests from Congress and federal investigators that they be preserved, the agency confirmed Tuesday in response to a subpoena from the House Jan. 6 committee.

Florida Rep. Stephanie Murphy, a Democratic member of the Jan 6. panel, said the Secret Service acknowledged the erasure in a letter Tuesday, detailing how agency phones were migrated to a new system in the weeks after the 2021 attack.

Murphy said the agency left it up to individual agents to decide what electronic records to keep and what to delete during the process.

"Nobody along the way stopped and thought, 'well, maybe we shouldn't do the migration of data and of the devices until we are able to fulfill these four requests from Congress,'" Murphy said on MSNBC.

The deletion of the messages has raised the prospect of lost evidence that could shed further light on then-President Donald Trump's actions during the insurrection, particularly after testimony about his confrontation with security as he tried to join supporters at the Capitol.

Murphy said that while the agency has turned over a large number of records and documents, what the committee is still seeking is the electronic communication between agents on the day before the attack and as a mob of rioters breached the Capitol building on Jan. 6.

"What they have also said is that they are going to continue to see if there are other ways in which they can secure the required and subpoenaed text messages that we have asked for," Murphy said. "My hope certainly is that they do find a way to find those texts and respond to the subpoena."

The Secret Service's response to the committee came the same day the National Archives requested that the agency investigate "the potential unauthorized deletion" of the texts.

In a series of Twitter posts on Wednesday, the Jan. 6 panel said that it had "concerns" about the system migration that led to the erasure of the texts, and said that the system for preserving records prior to the deletion "appears to have been contrary to federal records retention requirements and may represent a possible violation of the Federal Records Act."

"The Secret Service has begun producing records pursuant to the subpoena we issued last week and our investigators are assessing that information," the panel said in a statement. "We have concerns about a system migration that we have been told resulted in the erasure of Secret Service cell phone data."

"The U.S. Secret Service system migration process went forward on January 27, 2021, just three weeks after the attack on the Capitol in which the Vice President of the United States while under the protection of the Secret Service, was steps from a violent mob hunting for him," the statement continued.

"The procedure for preserving content prior to this purge appears to have been contrary to federal records retention requirements and may represent a possible violation of the Federal Records Act," the Twitter thread concluded. "The Select Committee is seeking additional Secret Service records as well."

The agency has been the target of heavy scrutiny following a letter sent last week by the Department of Homeland Security Office of Inspector General, obtained by The Associated Press, that told lawmakers that Secret Service messages between Jan. 5 and Jan. 6, 2021, were erased "as part of a device-replacement program."

The Secret Service has said all procedures were followed and pledged "full cooperation" with the Archives' review.

"The United States Secret Service respects and supports the important role of the National Archives and Records Administration in ensuring the preservation of government records," said agency spokesman Anthony Guglielmi.

The National Archives, which is in charge of government record-keeping, asked the Secret Service to investigate the possible erasure of the messages and report back within 30 days.

"Through several news sources, the National Archives and Records Administration (NARA) has become aware of the potential unauthorized deletion of United States Secret Service (Secret Service) text messages," Laurence Brewer, the chief record keeper for the U.S., said in a letter to the Department of Homeland Security.

If it is determined any text messages were deleted, the agency must detail what records were affected, a statement on the reasoning for deletion, plan for establishing safeguards to prevent future loss as well as "details of all agency actions taken to salvage, retrieve, or reconstruct the records," the letter read.

The Secret Service responded by telling AP that "the insinuation that the Secret Service maliciously deleted text messages following a request is false."

"In fact, the Secret Service has been fully cooperating with the OIG in every respect — whether it be interviews, documents, emails, or texts," Secret Service spokesman Guglielmi said.

He said the Secret Service had started to reset its mobile devices to factory settings in January 2021 "as part of a pre-planned, three-month system migration." In that process, some data was lost.

The nine-member House Jan. 6 panel has taken a recent, renewed interest in the Secret Service following the dramatic testimony of former White House aide Cassidy Hutchinson about Trump's actions on the day of the insurrection.