WATERVILLE — Fire officials are investigating the cause of a fire late Tuesday that destroyed a garage on Silver Street owned by Kennebec Behavioral Health.

Chief Shawn Esler of the Waterville Fire-Rescue Department said Wednesday the blaze was first reported at about 9:40 p.m. as a tree on fire, but firefighters then learned a building was on fire at 100 Silver St., the same address as an apartment building.

Firefighters found flames at the rear of the 1 1/2-story, two-bay garage used for storage, according to Esler. Firefighters were able to extinguish the fire quickly, he said.

“The fire appears to have originated in a designated smoking area and extended into the garage,” Esler wrote in an email. “Vegetation and leaves surrounding the garage contributed to the fire spread. The fire was contained to the building of origin.”

He said the fire is not considered suspicious and investigators are gathering more information.

“We will consider the fire undetermined until we speak with a few more people in the area,” Esler said.

He said the garage contained items for the apartment building, including furniture and building materials.

Winslow firefighters assisted city firefighters at the scene, and Oakland firefighters covered the city station, according to Esler.

No one was injured due to the fire, he said.