Several top officials in the Trump administration discussed highly sensitive military plans using an unclassified chat application that inadvertently included a journalist, the White House acknowledged Monday, a development that swiftly drew criticism from Washington’s national security establishment.

Brian Hughes, a spokesman for the White House National Security Council, said the message thread revealed in an extraordinary report by the Atlantic’s editor in chief, Jeffrey Goldberg, “appears to be authentic,” and that administration officials were “reviewing how an inadvertent number was added to the chain.”

The “inadvertent number” belonged to Goldberg, whose article details a robust policy discussion that occurred in the lead-up to a March 15 military operation targeting Yemen’s Houthi militants. Goldberg reported being added to the group chat, which occurred on the encrypted messaging platform Signal, by President Donald Trump’s national security adviser, Michael Waltz. Other participants included Vice President JD Vance, Defense Secretary Pete Hegseth and CIA Director John Ratcliffe, the Atlantic article says.

Hughes, the National Security Council spokesman, characterized the discussion as “a demonstration of the deep and thoughtful policy coordination between senior officials” executing Trump’s national security strategy. But the disclosure raises questions about how the administration has discussed classified issues and whether anyone will be disciplined.

Senior Trump administration officials have warned in recent days that they will investigate unauthorized leaks to journalists, citing reporting in a number of publications. Several of them also for years criticized the handling of classified information by Democrats in other cases.

The news was greeted by Democrats with exasperation and anger.

“If true, this story represents one of the most egregious failures of operational security and common sense I have ever seen,” Sen. Jack Reed (Rhode Island), the Senate Armed Services Committee’s top Democrat, said in a statement. “Military operations need to be handled with utmost discretion, using approved, secure lines of communication, because American lives are on the line. The carelessness shown by President Trump’s cabinet is stunning and dangerous. I will be seeking answers from the Administration immediately.”

Goldberg reported that he received an invitation to connect on Signal on March 11 from an account identified as belonging to Waltz. Goldberg, who has been criticized by Trump in the past, wrote in his article Monday that he assumed it was Waltz, but wondered whether it might also be someone pretending to be the national security adviser.

Two days later, Goldberg wrote, he received a notification through Signal that he was to be included in a group chat titled “Houthi PC small group,” an apparent reference to a principals committee meeting that typically includes Cabinet members and other senior national security officials. Several of the accounts appeared to designate subordinates as their representatives, including Andy Baker, Vance’s national security adviser, and Dan Caldwell, a senior Defense Department official.

Vance, according to the Atlantic article, said he thought the Trump administration was “making a mistake” by launching what U.S. military officials have since declared an open-ended operation against the Houthis. The vice president noted that about 3 percent of U.S. trade runs through the Suez Canal, where the Houthis have concentrated attacks on commercial shipping transiting the Red Sea, and that there is “real risk that the public doesn’t understand this or why it’s necessary.”

The Hegseth account, according to the Atlantic’s report, responded a short time later that he understood Vance’s concerns and fully supported the vice president raising them with Trump. The defense secretary then appeared to add that the “messaging is going to be tough no matter what” because “nobody knows who the Houthis are,” and so those plotting the operation should seek to convince the American public that “1) Biden failed & 2) Iran funded.” Those were apparent references to the Biden administration not being able to stop Houthi attacks, which the militant group began in response to Israel’s war in the Gaza Strip, and Tehran’s long-standing backing of the Houthis.

Contrary to Vance, Hegseth advocated military action, saying there was a risk that the Trump administration’s plans to attack could leak publicly or that Israel could take action against the militants first, leaving the administration unable to “start this on our own terms,” Goldberg recounted in his article.

As the bombing campaign moved ahead, Hegseth’s account shared details that Goldberg said he believed could put at risk the safety of U.S. troops or intelligence officials, especially those deployed in the Middle East. Those details, the Atlantic article says, allegedly included the specific weapons to be used and in which sequence the Houthi targets would be hit.

A spokesman for Hegseth, Sean Parnell, did not respond to requests for comment Monday. Hegseth had departed on a military aircraft for Asia shortly before the Atlantic story published.

Hegseth, a National Guard veteran and former Fox News host who did not previously hold senior positions in government, has said repeatedly that he will bring accountability back to the Pentagon.