Senior US official allows military information to leak through messaging app.

According to CNN, US officials reacted with "shock" to revelations in The Atlantic that senior members of President Donald Trump's Cabinet had sent detailed operational plans and potentially other classified information about US military airstrikes in Yemen to a discussion group on a messaging app, which a reporter was inadvertently added to.

The Trump administration acknowledged that messages sent through the non-governmental encrypted chat app Signal appeared authentic, but offered no explanation as to why senior officials were discussing defense information outside of approved classified government systems.

Almost immediately, senior officials quickly stepped in to review the use of Signal amid concerns that Trump administration officials were becoming too reliant on the app for sensitive government work—posing a serious risk to U.S. national security.

According to CNN, shortly after the story was published, it spread widely across many forums within the Trump administration, prompting officials to react with disbelief.

Many government officials told CNN they were shocked, with at least two speculating that this could lead to the firing of one of their colleagues. National security officials expressed deep disappointment in interviews with CNN, noting that having such sensitive conversations on an unclassified platform risks exposing information to foreign hackers – and any other employee who does so would almost certainly face immediate dismissal and possible prosecution.

According to The Atlantic, National Security Advisor Mike Waltz earlier this month convened a text message conversation with senior U.S. officials, including Vice President JD Vance, Defense Secretary Pete Hegseth, and Secretary of State Marco Rubio, to discuss attacks on Houthi forces in Yemen, who have threatened international shipping in the Red Sea. Waltz reportedly inadvertently added The Atlantic's editor-in-chief, Jeffrey Goldberg, to this group chat.

Signal is a popular encrypted messaging app used worldwide, including by journalists and government officials. Biden administration officials also frequently used it to discuss logistical plans for meetings and sometimes to communicate with foreign counterparts.

U.S. officials said that using Signal to discuss plans for military operations—one of the most closely guarded secrets—poses a shocking risk to national security.

President Trump has given no indication that he plans to fire anyone over the matter. He appeared surprised when asked about the story, telling reporters on the afternoon of March 24 (Washington time): "I don't know anything about it. I'm not a fan of The Atlantic. To me, it's a bankrupt magazine. I don't think it's a magazine. But I don't know anything about it."