If you thought storming into a highly secured government facility with your electronics but without permission was a smart idea, you’d be wrong.

But that didn’t stop Rep. Matt Gaetz and close to three-dozen of his Republican colleagues on Wednesday from doing exactly that.

Gaetz, a Republican congressman from Florida, proudly announced in his tweets: “I led over 30 of my colleagues into the SCIF where Adam Schiff is holding secret impeachment depositions.” At the time, Gaetz was interrupting a hearing of the House Intelligence Committee where the chairman, Schiff, was deposing a senior government official, Laura Cooper, as part of the Democrats’ impeachment inquiry into President Trump’s dealings with Ukraine.

One of the cardinal rules of entering one of these facilities is that you don’t bring in any electronics. And those lawmakers did exactly that.

A SCIF — a sensitive compartmented information facility — sounds fancy, but in reality are just rooms designed to be secure for sharing sensitive and secret information at the higher echelons of government secrecy. There are plenty dotted around Washington, DC for lawmakers and government officials to huddle in and chit-chat. There are SCIFs in the White House, Congress and every major government department in the capital — even the president’s Florida resort.

The idea is you go in to one of these rooms and they’re safe to discuss state secrets. These rooms vary by size and shape — some are enormous and are able to accommodate an entire congressional committee. Some can be used on the road in the form of a large pop-up tent. But they all do the same job: they’re designed to a specification so that nobody can eavesdrop on what’s being said.

So when a gaggle of Republican lawmakers stormed one of the congressional SCIFs yesterday with their electronics in their pockets, understandably a lot of people were furious.

“No unauthorized electronic devices are allowed in the SCIF precisely because they could be used to exfiltrate decoded, highly classified data,” said Alan Woodward, a professor at the University of Surrey. “Standard operating procedure is to deposit anything like a mobile phone in some storage outside before entering,” he said.

“To force your way into a SCIF and use a mobile device inside is the height of recklessness: you must know that you are endangering material that could cause grave damage to the national interest,” he added.

The rebuke was quick.

“[The lawmakers] endangered our national security and demonstrated they care more about a political stunt than protecting intelligence information,” tweeted Mieke Eoyang, vice-president of Third Way, a national security think tank. “Foreign adversaries are constantly trying to figure out what goes on inside those rooms to figure out what the U.S. knows about them, to out U.S. high-level sources in their governments, to know what the U.S. government knows and use it against us,” she said.

“I cannot emphasize enough how serious this is,” she added.

And neither can the chairman of the House Homeland Security committee, Rep. Bennie Thompson (D-MS), who wrote to the Sergeant-at-Arms, the official in charge of the House’s law enforcement, expressing his anger at the infraction.

“Such action is a blatant breach of security,” said Thompson in the strongly worded letter, demanding action be taken against the violating House members.

“Inadvertently bringing electronics into a SCIF is a very common security infraction, and it is taken incredibly seriously by agencies,” said Mark S. Zaid, an attorney specializing in national security cases. “It is drilled into people’s heads to never bring their cell phone into a protected area.”

The penalties for the House members could be swift, said Zaid, including pulling their future access to classified material.

“Agencies will not hesitate to revoke someone’s security clearances when multiple infractions occur,” he said. “When it comes to intentional infractions, the repercussions would be swift and severe, as it should be.”

An earlier version of this article said Gaetz deleted his tweets, but they were not. We regret the error.