An apparent accidental fire Saturday evening caused significant damage in the Mill Creek condominiums in Keystone, but a sprinkler head kept it from spreading, and no one was injured.

Some 15 firefighters from Lake Dillon Fire responded to an alarm triggered by the sprinkler system about 7:15 p.m., and they were assisted by a crew from Red, White & Blue Fire of Breckenridge in extinguishing the fire. They were supported by two volunteers from the Lake Dillon Fire Corps.

The fire caused significant damage to two units and left two others with smoke and water damage. Keystone Resorts found alternative lodging for the people staying at the six-unit building at 56 River Run Road.

The fire apparently broke out in the concealed space between the third and fourth floors, and the initial focus of the investigation is on electrical wiring.

“Fortunately, everything worked as it should: A single sprinkler head kept the fire from spreading, and the alarm alerted the occupants. And, most importantly, the occupants heeded the alarm and evacuated the building immediately,” said Lake Dillon Fire Chief Jeff Berino.

A preliminary estimate of the total damage is between $400,000 and $500,000.