MORTON, MINN. – The slot machines fell silent over the weekend at Jackpot Junction Casino Hotel.

Guests starting Thursday began noticing phones not working, bingo night cancellations and reservations that they could not change.

The casino took some systems offline after a cyberattack affecting the Lower Sioux Indian Community, said Robert "Deuce" Larsen, president of the community's council, which runs the casino.

"Jackpot Junction recently identified a cybersecurity incident involving unauthorized access to certain systems," Larsen said in a post on Facebook Monday night.

The casino is working with "third-party experts," Larsen said.

A criminal group named RansomHub claimed an attack on the casino in a message on the dark web posted on Monday, according to three online websites that track cyber gangs.

RansomHub is a prolific criminal group likely based in Russia, said Luke Connolly, an analyst with the cybersecurity firm Emsisoft. The group has claimed hundreds of victims since its founding in February 2024.

Cyber gangs will often post the names of their victims, hoping to embarrass them or as part of a threat to release more information, Connolly said.

Casinos have proved to be ripe targets for hackers. A data breach at MGM Resorts in Las Vegas in 2023 shut down slot machines and leaked customer data. The breach led to a $100 million hit to the company's finances, a CNN report said. And tribal casinos in Michigan have shut down due to attacks earlier this year.

Phone lines at the casino remained down as of Tuesday afternoon, and the parking lot was empty.

Guests were unable to call the hotel to talk about their reservations and had to communicate via Facebook, said Lora Weilage Delozier, 55.

Delozier drove in from St. Cloud with her son on Friday. She said that when she checked in to the hotel on Friday, a staff member had to escort her to her room so they could open it.

Delozier said she left Saturday afternoon after realizing the slot machines had been shut down.

Teachers at the community's Head Start program have been using a text and messaging system to keep parents informed, said Tricia Baune, education coordinator and director of the program, C̣aƞṡayapi Waḳaƞyeża Owayawa Oṭi.

Calls to the Lower Sioux Health Care Center were not going through as of Tuesday morning.

The casino's bar, restaurants and game tables have remained open during the outages.

And the band played on: the Oak Ridge Boys and Phil Vassar played country tunes at the casino on Saturday night.