Just minutes before U.S. airstrikes began against Iranian-backed Houthi rebels in Yemen last month, Gen. Michael Erik Kurilla, head of U.S. Central Command, sent operational details—including takeoff and target times—via a secure channel to Defense Secretary Pete Hegseth. The system was designed for precisely this kind of sensitive military coordination.

But Hegseth, according to multiple U.S. officials, relayed some of that information using his personal phone through two Signal group chats. One included Cabinet-level officials and inadvertently the editor of The Atlantic. The second included his wife, brother, attorney, and aides. The messages were sent less than 10 minutes after Kurilla’s transmission.

Despite prior warnings from aides not to use insecure platforms before the operation, Hegseth pressed forward. The Pentagon insists no classified material was shared, and spokesman Sean Parnell dismissed the incident as a smear campaign. Hegseth echoed that stance during a Fox & Friends appearance, stating the messages were “informal, unclassified coordinations.”

President Trump, who appointed Hegseth despite bipartisan skepticism over his qualifications, stood by him during the White House Easter Egg Roll, saying, “Pete’s doing a great job.” Hegseth, unfazed by growing criticism, dismissed the reporting as attacks by disgruntled ex-employees.

Still, the backlash is growing. Rep. Don Bacon, a Nebraska Republican and retired Air Force general, became the first GOP lawmaker to call for Hegseth’s resignation, citing his lack of experience. Meanwhile, two Trump advisers said there’s no active discussion of removing him, reaffirming the president’s support.

A former Trump administration official expressed alarm at the breach, especially the decision to share strike details with family. “It’s baffling,” the official said. “Doing so over an unclassified app is even more egregious.”