Pentagon opens investigation into messaging-app use by Defence Secretary

US Secretary of Defense Pete Hegseth waits for the arrival of Japan's Prime Minister Shigeru Ishiba prior to their meeting at the Prime Minister's office in Tokyo on March 30, 2025. The United States will ensure "robust, ready and credible deterrence" across the Taiwan Strait, US Defense Secretary Pete Hegseth said on March 30, calling China "aggressive and coercive". Stanislav Kogiku / POOL / AFP

The United States Department of Defense has launched an investigation into Defence Secretary Pete Hegseth’s use of the messaging app Signal.

The Pentagon’s Inspector General said that the evaluation aimed to determine the extent to which the Secretary and other staff adhered to policies and procedures for using commercial messaging services for official business.

In late March, it was revealed that Hegseth shared details, in a Signal group, about a planned US attack on Houthi rebels in Yemen. The Atlantic’s Editor-in-Chief, Jeffrey Goldberg, had been accidentally added to this group.