The House panel investigating the U.S. Capitol insurrection is holding a surprise hearing on Tuesday with an unidentified witness, cloaking the last-minute proceedings in extraordinary secrecy and raising expectations for new bombshells in the sweeping investigation into the Jan. 6, 2021, attack.

The unexpected hearing, scheduled for 1 p.m. Tuesday, was announced with 24 hours’ notice while lawmakers are away from Washington on a two-week recess. The committee had said last week that there would be no more hearings until July.

The subject of the hearing is so far unclear, but the panel’s announcement on Monday said it would be “to present recently obtained evidence and receive witness testimony.” A spokesman for the panel declined to elaborate.

The committee’s investigation has been ongoing during the hearings, which started three weeks ago, and the nine-member panel has continued to probe the attack by supporters of then-President Donald Trump. Among other investigative evidence, the committee recently obtained new footage of Trump and his inner circle taken both before and after Jan. 6 from British filmmaker Alex Holder.

Holder said last week that he had complied with a congressional subpoena to turn over all the footage he shot in the final weeks of Trump’s 2020 reelection campaign, including exclusive interviews with Trump, his children and then-Vice President Mike Pence. The footage includes material from before the insurrection and afterward.

It is uncertain if Holder’s footage will be shown at the hearing Tuesday. Russell Smith, a lawyer for Holder, declined to comment.

Rep. Bennie Thompson of Mississippi, the panel’s Democratic chairman, told reporters last week that the committee was in possession of the footage and needed more time to go through the hours of video.

The panel has held five hearings so far, mostly laying out Trump’s pressure campaign on various institutions of power in the weeks leading up to the Jan. 6 joint session of Congress, when hundreds of the Republican’s supporters violently pushed past police, broke into the building and interrupted the certification of Democrat Joe Biden’s presidential election victory.

The committee has used the hearings to detail the pressure from Trump and his allies on Pence, on the states that were certifying Biden’s win, and on the Justice Department. The panel has used live interviews, video testimony of its private witness interviews and footage of the attack to detail what it has learned.

Lawmakers said last week that the two July hearings would focus on domestic extremists who breached the Capitol that day and on what Trump was doing as the violence unfolded.

(AP)