Slot machines and ATM machines were also inoperable, elevators were out of order and customers had to wait hours to check into rooms.
Hackers struck MGM Resorts on Sunday morning, rendering doors to the chain's casinos and hotels unusable.
Five days after a cyberattack crippled operations of MGM Resorts International, including its signature Las Vegas properties the Bellagio and the MGM Grand, the company said Thursday morning it is still working to resolve issues as another major resort operation, Caesars Entertainment, acknowledged it was also the target of a cyberattack.
