On Monday morning, MGM Resorts announced in a social media post that it had discovered a “cybersecurity issue” in its computer systems. 

The company responded by shutting down its computer systems in order to protect data.

The shutdowns disrupted the day-to-day operations of MGM’s casinos and resorts in Las Vegas, as well as across the country in states such as Massachusetts, New Jersey and New York, a MGM spokesperson told the Associated Press. 

At the time of publication, the MGM Resorts homepage remains down. (Other MGM sites, like the careers and media pages, stayed online.) Bloomberg reported that some restaurants at MGM properties are only accepting cash, some slot machines weren’t functional and that staff checked in hotel guests manually by writing down credit card numbers with pen and paper.

On Monday night, MGM Resorts released an update that its “resorts, including dining, entertainment and gaming are currently operational.”

The company’s announcement conflicted with some guests’ on-the-ground experiences. Chris Holmes, who runs an aerial imaging company out of Las Vegas, passed through the Aria, Bellagio, MGM Grand and New York-New York casinos around 8 a.m. Wednesday morning, and noted lingering issues with slot machines. 

“People [try] to gamble, and the machines say ‘not in use,’ and they’re befuddled why they can’t get their money back,” Holmes told SFGATE. 

The shutdowns come with some unexpected perks — notably, free parking, which is no longer guaranteed in Las Vegas. Holmes said that at the MGM casinos he visited, parking garage gates were operating unusually. “There were still spitting out tickets, but on the way out, the arms were up,” he said. “They weren’t taking payments or anything.”

MGM Resorts contacted law enforcement, the company wrote in its initial statement. The Associated Press reported that the FBI has opened an investigation.

The company did not return a request for comment in time for publication.