WASHINGTON (AP) — The House Jan. 6 committee has interviewed former Treasury Secretary Steven Mnuchin and is in negotiations to talk to several other former members of Donald Trump’s Cabinet as it scrutinizes the days after the Capitol insurrection and discussions about whether to try and remove the then-president from office.

The negotiations come as the committee was interviewing Trump’s onetime chief of staff, Mick Mulvaney, on Thursday. The former South Carolina congressman held that job until 2020 and later was special envoy for Northern Ireland, a post he resigned immediately after the riot on Jan. 6, 2021.

The interviews and negotiations were confirmed by three people familiar with the committee’s work who were not authorized to discuss the developments publicly and spoke on condition of anonymity.

The committee asked Mnuchin about discussions among Cabinet secretaries to possibly invoke the constitutional process in the 25th Amendment to remove Trump after the attack on the Capitol, according to one of the people, and is in active talks to interview former Secretary of State Mike Pompeo. Pompeo is likely to appear in the coming days, the person said.

The committee had already interviewed former acting Attorney General Jeffrey Rosen, former Labor Secretary Eugene Scalia and former acting Defense Secretary Christopher Miller as it focuses on Trump and what he was doing in the days before, during and after the riot.

Lawmakers also are in discussions with John Ratcliffe, former director of national intelligence, according to two of the people, and are seeking interviews with several senior intelligence officials who had contact with the White House around that time.

Ratcliffe delivered a classified briefing on election security in late December 2020 at the request of Jeffrey Clark, a Justice Department official who promoted Trump’s false claims of election fraud.

A person familiar with the matter said Ratcliffe summarized the findings of an election security report that said intelligence agencies had “no indications that any foreign actors attempted to alter any technical aspect of the voting process in the 2020 U.S. elections, including voter registration, casting ballots, vote tabulation, or reporting results.”

Trump and outside advisers who were pushing the false fraud claims had suggested that Venezuela had somehow tried to alter the count through voting machines.

The focus on the Cabinet is one of several threads the committee is pursuing after laying out much of its evidence in eight hearings this summer. After a yearlong investigation and more than 1,000 interviews, committee members say there is much more they want to learn.

The committee is expected to convene additional hearings in September.

Investigators have also reached out to former Homeland Security Secretary Chad Wolf, who resigned in the days after the riot, and lawmakers could call in other Trump Cabinet officials.

Betsy DeVos, Trump’s education secretary at the time, previously told USA Today that she raised with Vice President Mike Pence the question of whether the Cabinet should consider invoking the 25th Amendment, which would have required the vice president and the majority of the Cabinet to agree that the president could no longer fulfill his duties.

DeVos resigned the day after the attack, blaming Trump for inciting the mob.

“There is no mistaking the impact your rhetoric had on the situation, and it is the inflection point for me,” she wrote.

At a rally on the morning of Jan. 6, Trump had told a crowd of his supporters to “fight like hell” as Congress met to certify Joe Biden’s election victory, and the rioters were repeating Trump’s false claims as they broke into the Capitol and violently pushed past police.

Elaine Chao also quit as transportation secretary on Jan. 7. Chao, who is married to Senate GOP leader Mitch McConnell of Kentucky, said the attack had “deeply troubled me in a way that I simply cannot set aside.”

Pompeo, who is now considering a 2024 presidential run, and Mnuchin were reported to have discussed the possibility of invoking the 25th Amendment, according to Jonathan Karl of ABC News in his book “Betrayal.”