A third official is out at the Pentagon as part of Defense Secretary Pete Hegseth‘s massive crackdown on leaks.
Colin Carroll, chief of staff to Deputy Defense Secretary Stephen Feinberg, was suspended a day after two other political appointees were shown the door, Politico reported.
The internal Pentagon investigation was looking into allegations of unauthorized disclosures of information.
Dan Caldwell, a senior adviser to Hegseth, and Darin Selnick, the Pentagon’s deputy chief of staff, were put on administrative leave and escorted out of the Pentagon by security on Tuesday.
‘This is a purge of people who had disagreements with the Pentagon chief of staff,’ a defense source told CNN.
President Donald Trump has railed against leakers, particularly those leaking information about his administration. He has ordered them found.
Colin Carroll (right), chief of staff to Deputy Defense Secretary, has been suspended as part of a leak investigation
Carroll, a former Marine Corps intelligence officer with deep AI expertise, served in Afghanistan. He is a graduate of the United States Naval Academy.
Ahead of his tenure at the Pentagon, Carroll worked at Anduril, a defense contractor that specializes in autonomous systems.
He was fired by the Biden administration for creating a hostile environment while chief operating officer of the Pentagon’s former Joint Artificial Intelligence Center.
Hegseth’s chief of staff, Joe Kasper, ordered the leak investigation in a March 21 memo to defense department staff.
The leaks under investigation included military operational plans for the Panama canal, a second carrier headed to the Red Sea, the pausing the collection of intelligence to Ukraine, and the leak that Elon Musk’s would meet with Hegseth about the U.S. war plans for China, an official told Politico.
Kasper said the probe would examine ‘recent unauthorized disclosures of national security information’ and said polygraphs would be used.
‘The use of polygraphs in the execution of this investigation will be in accordance with applicable law and policy,’ he wrote. ‘This investigation will commence immediately and culminate in a report to the Secretary of Defense.’
He noted that ‘information identifying a party responsible for an unauthorized disclosure’ would be referred for criminal prosecution.’
Kasper ordered the probe one day after the New York Times reported the Pentagon set up a briefing with Elon Musk on a potential war with China.
Although Caldwell is not as well known as other senior Pentagon officials, he has played a critical role as an adviser to Hegseth.
He was the staff member designated as Hegseth’s point person in the Signal messaging chat that top Trump administration national security officials, including Hegseth, used to convey plans for a military strike against Houthi militants in Yemen.
The chat, set up by national security adviser Michael Waltz, included a number of Cabinet members and came to light because Jeffrey Goldberg, editor-in-chief of The Atlantic, was accidentally added to the group.
Top Defense aides Dan Caldwell (left) and Darin Selnick (right) were escorted out of the Pentagon on Tuesday after allegedly being identified during the leak investigation
Defense Secretary Pete Hegseth (foreground) with Secretary of State Marco Rubio and President Donald Trump in the Oval Office
Caldwell and Hegseth have a longtime friendship.
His ties to the secretary go back to Hegseth’s time as the head of Concerned Veterans for America, a nonprofit. Caldwell worked at CVA beginning in 2013 as policy director and later as executive director.
Caldwell was by Hegseth’s side on Capitol Hill as the former Fox News host fought to keep his nomination alive during questions about his treatment of women.
Selnick also performed the duties of the under secretary of Defense for personnel and readiness. He served in the White House and the Department of Veterans Affairs in the first Trump administration.
And he also has ties to Concerned Veterans for America, where he served as a senior adviser.
All three suspended aides are close in age and share the same isolationist view of foreign policy. That view is also shared by Vice President J.D. Vance and Don Trump Jr., the president’s oldest son.
