A small fire at the Hard Rock Hotel & Casino forced part of the resort to be evacuated on Sunday, just before 4 p.m.

The fire was started by an air conditioning unit overheating in a wall between the existing resort and a new building being built on site.

There were no fire alarms in the area where the fire flared up, but the heavy smoke alerted security and guests.

"All hell broke loose. We thought it was a bomb scare and they told us to go out of there. We didn't know what was going on," said Gil Nugent, who was told to leave from the sports book.

As a precaution, the hotel and casino evacuated nearby guests into a back parking lot.

Firefighters ripped open part of the wall to reach the fire.

"The water that was applied to put of the fire, went down obviously into the first floor. Then smoke that generated went up into the 3rd, 4th and 5th floor. It was minor damage both from the water and the smoke," said Chief Jon Klassen, with the Clark County Fire Dept.

No one was injured in the fire.  We're told one hotel security worker did go to the hospital for heat exhaustion.

He's expected to be just fine.

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