A photo taken this week showed Mike Waltz using an app that looks like—but is not—Signal to communicate with top officials.

Former national security adviser Mike Waltz was photographed using a Signal-like messaging app during Wednesday’s Cabinet ...

Former national security adviser Mike Waltz was photographed using a Signal-like messaging app during Wednesday’s Cabinet ...

President Donald Trump's outgoing national security adviser Mike Waltz was photographed peaking at his phone under the table ...

Mike Waltz was photographed using Signal in a Cabinet meeting the day before Trump announced he was replacing him as national ...

Former national security adviser Mike Waltz was photographed using the Signal app during a Cabinet meeting on Wednesday, a ...

Waltz was at the center of the Signal chat controversy, in which a journalist was accidentally included in a discussion of ...

Democrats are preparing to grill Mike Waltz about the Signal chat scandal when he appears at a confirmation hearing to be the ...

National security adviser Mike Waltz is leaving his White House post, although soon after reports about his departure were ...

A photo of Mike Waltz's phone appeared to show that he was using TeleMessage, an app that modifies Signal and other ...

NewsNation's Washington, D.C. correspondent Joe Khalil provides the latest on the surprise shuffle in President Trump's ...

Waltz was among high-ranking members of the administration who accidentally shared plans about a forthcoming U.S. military ...