A phone app that Mike Waltz, President Donald Trump’s former national security adviser, apparently used to save his text messages has temporarily suspended its services as it investigates a cybersecurity incident,

An encrypted messaging app used by the Trump administration temporarily suspended its operations Monday after suffering a massive hack. TeleMessage, a platform that archives messages sent through apps like Signal,

Last week, however, Waltz’s phone made headlines again: on Thursday, the same day that Waltz would be ousted from his position, a Reuters photographer captured an image that showed him checking Signal messages from colleagues beneath a table at a cabinet meeting.