LAS VEGAS >> Officials say a power outage has forced the evacuation of 900 rooms at the Rio casino in Las Vegas.

Spokesman Richard Broome of the Rio’s parent company, Caesars Entertainment, said the evacuations happened around 7 a.m. today when a fuse blew in a backup generator that was powering the hotel’s Masquerade Tower.

The outage affects the fire control systems, so officials are making patrons leave their rooms.

Broome said patrons are being directed to the Rock of Ages lounge, where they’re getting food, beverages and updates about the situation. He said it’s too early to say when the power will be restored and whether guests will be compensated for the inconvenience.

The backup generator was on after a small electrical fire Wednesday night compromised the main power source.