The U.S. congressional committee probing the deadly Jan. 6 assault on the Capitol threatened former President Donald Trump"s White House chief of staff on Thursday with a criminal contempt referral if he does not appear before the panel and hand over required documents by Friday morning. If former chief of staff Mark Meadows does not produce the documents and appear for testimony at 10 a.m. EST (1500 GMT), the House of Representatives Select Committee will view his actions as willful non-compliance, the panel"s Democratic chairman, Representative Bennie Thompson, said in a letter to Meadows" attorney. The committee announced in September that it had subpoenaed Meadows, citing reports the former House member had communicated with state and federal officials - including members of Congress - as part of an effort to overturn the Republican Trump"s defeat in the 2020 presidential election by Democrat Joe Biden. It said then it wanted Meadows to testify and hand over documents by mid-October. The two sides had been negotiating since. Thompson said Meadows has not produced even a single document. "Although you previously indicated that your firm was searching records that Mr. Meadows provided to you, more than enough time has passed for you to complete your review," the letter to Meadows" attorney George Terwilliger said. Thompson said willful noncompliance with its subpoena could result in a referral from the House to the Department of Justice for criminal contempt charges, as well as the possibility of having a civil action to enforce the subpoena brought against Meadows. The House voted last month to hold Trump senior adviser Steve Bannon in contempt and refer his case to Justice. Terwilliger did not immediately respond to a request for comment. He had issued a statement earlier on Thursday suggesting Meadows would not cooperate with the committee until all legal disputes were resolved. Trump has filed suit to avoid turning over White House documents and urged former aides to reject subpoenas.