The Pentagon watchdog concluded that Defense Secretary Pete Hegseth may have put US troops at risk when he shared attack plans on the Signal messaging app from his personal phone, according to a person familiar with the matter.

The acting Pentagon inspector general’s report, delivered to Congress this week, found that the US mission and servicemembers could have been endangered if a foreign adversary had intercepted the messages sent by Hegseth, according to the person, who saw the document. The report said that he violated government policies by using his personal device.