The team of President Donald Trump's national security adviser, Mike Waltz, set up at least 20 group chats on the commercial Signal app to coordinate official work on issues involving China, Gaza, Middle East policy,

The national security adviser's use of the messaging app is under scrutiny after he mistakenly added a journalist to a sensitive chat.

Reports of 20 Signal chats and Waltz’s Gmail mark at least four major security liabilities uncovered since Signalgate.

Jimmy Kimmel unloaded on the Trump administration over Signalgate last Thursday, calling the scandal a "perfect storm of incompetence."

The Atlantic's editor-in-chief Jeffrey Goldberg reported he was accidentally added by Mike Waltz to a group chat containing secret military plans.

President Trump's national security adviser has denied knowing the editor of The Atlantic after accidentally adding him to a sensitive group chat.

Although Trump decided not to fire his national security adviser over the Signal group chat, Waltz’s position is tenuous, officials say.

It’s a more extensive use of the app than previously reported and sheds new light on how commonly the Trump administration’s national security team relies on Signal.