The person whom former President Donald Trump was accused of having contacted following the Jan. 6 hearing when former administration aide Cassidy Hutchinson testified was a member of the White House support staff, sources told ABC News.
Trump's alleged contact with the individual was described on Tuesday by the House Jan. 6 committee's vice chair, Wyoming Republican Rep. Liz Cheney, who did not name the person.
"After our last hearing, President Trump tried to call a witness in our investigation -- a witness you have not yet seen in these hearings," she said at the close of the most recent committee hearing.
Cheney said the witness did not answer the call.
"Their lawyer alerted us, and this committee has supplied that information to the Department of Justice," she said.
"Let me say one more time, we will take any effort to influence witness testimony very seriously," Cheney added, as the committee continually warns against witness tampering in its ongoing investigation.
This person was not someone Trump would typically call. Many members of the support staff are those who work from administration to administration and would have not necessarily left when Trump left office.
When asked Tuesday night how he knew that the alleged phone call from Trump to a witness amounted to witness tampering, the committee chair, Mississippi Democrat Bennie Thompson, said "I don't" and that's why they alerted the DOJ.
CNN first reported the new details about the witness.
ABC News' Libby Cathey contributed to this report.