LAS VEGAS -- Las Vegas Fire and Rescue said a two-alarm fire in a one-story town home was started by an air conditioner and was ruled accidental.

The report came in at 11:31 p.m. Friday.

The blaze began around an air conditioning unit mounted on the roof of a home at Springhurst Townhouses at 3000 El Camino Ave., fire officials said.

The blaze was upgraded to a two-alarm fire just before noon.

The occupants said the air conditioner stopped working, so they called the landlord. The occupants said they smelled something but thought it was bug spray. The landlord came to the front door and noticed smoke beginning to come out around the air conditioner on the roof, fire officials said.

The residents were not aware of the fire. They left the building and called 911, officials said.

When firefighters arrived, they said heavy smoke and flames were coming from the roof. The blaze was quickly brought under control, with damage contained mostly to the attic and roof, they said. Most of the occupants’ possessions were saved by firefighters.

There were no injuries.

Two adults and a dog lived in the town home. The adults are being assisted by the American Red Cross, and the dog is staying with family members.

Officials said there was some debris in the living area, heavy damage to an office area and heavy fire damage to the roof and attic.

Damage was estimated at $150,000.