U.S. Coast Guard Commandant Adm. Linda Fagan, the first female uniformed leader of an armed forces branch in U.S. history, was ousted by the Trump administration with no explanation late Monday.

Acting Secretary of Homeland Security Benjamine Huffman relieved Fagan of her duties as Coast Guard commandant, noting she “served a long and illustrious career, and I thank her for her service to our nation,” according to a message sent to all Coast Guard members Tuesday. 

Adm. Kevin Lunday, the former vice commandant of the Coast Guard, will take over as acting commandant, the statement notes, offering no other details of the switch.

The Coast Guard referred questions to the Department of Homeland Security (DHS), which did not respond as of press time.

An online biography on Fagan was unavailable Tuesday morning, and the Coast Guard’s official website listing the service’s senior leadership showed a blank space under “Commandant.”

Fagan, also the Coast Guard’s first female four-star admiral, had served as the military branch’s 27th commandant since June 1, 2022, after former President Biden chose her to lead the service  of 42,000 active-duty, 7,000 reserve and 8,700 civilian personnel.

But a senior DHS official told Fox News that Fagan was relieved due to border security concerns, recruitment and acquisition issues and an “erosion of trust” following an internal investigation into sexual assault cases at the Coast Guard Academy. 

At the time she took over, Fagan adopted a force that for years had struggled to meet its recruiting goals including under President Trump during his first term. But the Coast Guard was able to meet its goal just last year after it brought on more recruiters.

Also under Fagan, the Coast Guard was hit with a major controversy with Operation Fouled Anchor, an internal probe led by the branch investigating sexual misconduct at the Coast Guard Academy in Connecticut between 1988 and 2006. The investigation, closed in January 2020 during Trump’s first administration, was not voluntarily disclosed to Congress or the public by the Coast Guard until 2023 after being withheld by the service’s commandant at the time, Adm. Karl Schultz. 

Fagan, who was grilled over the report by senators in June, acknowledged the service’s “failure to share the report with Congress was a mistake.”

Her firing is the first of several personnel changes expected to affect several top U.S. military members, as Trump has promised to oust the generals and admirals he has deemed “woke.”

And Pete Hegseth, Trump’s nominee to lead the Pentagon, has said eliminating diversity and equity efforts in the military will be a top priority if he’s confirmed.

Joint Chiefs of Staff Chair Gen. CQ Brown Jr., whom Trump had threatened to fire once in power, said Monday he plans to remain in his role as the country’s highest-ranking military official.

Updated at 12:20 p.m. EST