The Defense Department's internal watchdog is investigating Defense Secretary Pete Hegseth's use of the messaging app Signal to discuss highly sensitive military information, according to a newly released memo.

The probe will look at whether Hegseth complied with all DOD policies when he used a group chat to discuss details of a strike against Houthi militants in Yemen last month. In addition to other Trump administration officials, the group accidentally included a prominent journalist. 

The inspector general will also review whether Hegseth violated any rules regarding classified information. Critics have alleged the details he shared included classified material, which Hegseth denies. 

The watchdog opened the probe after a request from leaders of the Senate Armed Services Committee. 

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