The U.S. Secret Service has given the House Jan. 6 committee a listing of agency-issued cell phone numbers belonging to agents based in Washington, D.C., for the period the panel is investigating, according to sources familiar with the matter.
The move is an unusual step amid heightened scrutiny of the agency's cooperation with the congressional panel investigating last year's insurrection and the role then-President Donald Trump played in it.
The committee can now determine which agents' call records they may want to review and, if they decide to do so, could either request them directly or conceivably issue subpoenas to their cell phone providers, an official familiar with the situation explained.
At the same time, the inspector general responsible for the Secret Service has obtained a listing of personal cell phones as part of its own investigation connected to the Jan. 6 attack on the Capitol.
MORE: Secret Service deleted texts from Jan. 5 and 6, 2021, after watchdog sought recordsThe Secret Service and Department of Homeland Security, which oversees the agency, have faced criticism in recent weeks for wiping text messages belonging to agents on and around Jan. 6, 2021. Congressional Democrats have accused the Homeland Security inspector general of abandoning efforts to collect text and phone records from that day.
Seeking and obtaining information from personal devices from federal workers is a "highly unusual" step, according to ABC News contributor Don Mihalek, a retired senior Secret Service agent, and could reflect a renewed effort by the agency to further demonstrate its cooperation with congressional investigators.
MORE: Secret Service provides Jan. 6 committee single text exchange from that dayThe Secret Service has faced serious criticism in recent weeks as committee testimony focused on Trump's conduct on Jan. 6, 2021, and what agents assigned to the White House did and saw that day.
At the same time, Mihalek said, the agency's decision to hand personal device information over to the committee could present thorny legal challenges.
MORE: Secret Service says no new Jan. 6 texts found after records were deleted; investigation requestedA spokesperson for the Secret Service recently acknowledged that some phone data from January 2021 was lost as the result of a pre-planned data transfer, noting that the transfer was underway when the inspector general's office made the request in February 2021.
ABC News reported Thursday that DHS is reviewing its electronic retention policies and would halt wiping political appointees' phones until the review is complete.
The Secret Service and representatives of the Jan. 6 committee declined to comment.
ABC News' Aaron Katersky and Luke Barr contributed to this report.