A senior FBI official who briefly served as acting director in the early days of the Trump administration is being ousted from the bureau amid a sweeping leadership purge, two sources familiar with the matter said Thursday. Brian Driscoll, a veteran agent with extensive counterterrorism experience, is expected to leave the FBI on Friday. While the exact circumstances of his removal remain unclear, his exit comes as the FBI undergoes major internal restructuring under Director Kash Patel and Deputy Director Dan Bongino.

Driscoll most recently served as acting director of the bureau’s Critical Incident Response Group, which oversees deployments during national crises. He had also previously led the elite Hostage Rescue Team and managed high-profile international investigations out of the New York field office. In January, he was appointed acting director while Patel’s nomination was pending following the departure of Christopher Wray.

Driscoll drew national attention earlier this year when he and then–Deputy Director Rob Kissane resisted pressure from Trump administration officials to turn over the names of FBI agents who had participated in the investigation into the January 6, 2021, Capitol riot. Instead, the bureau provided anonymized data—identifying agents by unique employee numbers—in response to a request from senior Justice Department official Emil Bove, who later accused FBI leadership of “insubordination” in a memo. Bove was confirmed last week to a seat on the federal appeals court.

The FBI’s internal upheaval under Patel and Bongino has included the reassignment or forced resignation of numerous senior officials, including special agents in charge of several major field offices. Some agents have also reportedly been subjected to polygraph exams, a move that former officials say has shaken morale and deepened internal distrust.

One such reassignment occurred in April, when several agents who had been photographed kneeling during a 2020 racial justice protest in Washington were removed from their posts, sources said. Another agent, Michael Feinberg, said he was pressured to resign or accept demotion after leadership raised concerns over his association with Peter Strzok, the former lead agent in the Trump-Russia investigation who was fired in 2018 over politically charged texts.

The FBI declined to comment on Driscoll’s departure or the wider leadership reshuffle. However, additional personnel changes are reportedly under consideration.

This article includes reporting by the Associated Press.

This is a breaking news story. Updates to follow.