A single-story structure about 200 yards mauka of Maui’s Honoapiilani Highway went up in flames Saturday morning, Maui County officials said. 

Firefighters arrived on scene in the Olowalu area near mile post 16 just before noon. 

Officials said a passing driver reported the blaze that sparked up in the 20-by-20-foot building situated in heavy brush.

No other structures were present in the area, and the fire was contained to that small building. Officials said no one was in the structure at the time of the fire, so there were no injuries.

The cause of the fire is undetermined. Officials said there is no damage estimate because the building, on land owned by West Maui Land Co., was an unpermitted structure.