Jeffrey Goldberg, the editor of The Atlantic, said he was mistakenly added to a group chat with U.S. national security leaders about imminent military strikes on Yemen.

Democratic lawmakers swiftly blasted the misstep saying it was a breach of U.S. national security and a violation of law that must be investigated by Congress.

The White House confirmed to the Daily Caller on Monday that President Donald Trump’s national security team accidentally leaked war plans to The Atlantic in a group chat. The Atlantic Editor-in-chief Jeffrey Goldberg published a piece on Monday detailing how he had been accidentally included in group chat with cabinet officials on Signal,