A radio transmitter building on North Madison Avenue was destroyed in a fire early Monday morning.

The fire was discovered by Bainbridge Police Officer Trevor Ziemba while he was on patrol in the area and smelled smoke.

Ziemba soon pinpointed the property where the source of the smell was coming from, and the Bainbridge Island Fire Department was called in to put out the blaze.

The fire appeared to start in a radio transmitter building located at the base of a radio tower on the property, but spread from the 12-foot-by-12-foot structure to nearby grass and then started a brush fire.

The fire burned a grassy area about 50-foot square before it was doused by firefighters.

Bainbridge Island Fire Marshal Luke Carpenter said the cause of the fire has not yet been determined.

It could have been worse, he added, given the recent dry spell on Bainbridge Island.

Carpenter praised Ziemba for tracking down the source of the smoke so quickly.

“It’s hot and hasn’t rained for a while, so that fire had the ability to really take off if it hadn’t been detected as soon as it was,” Carpenter said.

The fire was reported at 9:23 a.m., and firefighters had it completely extinguished in about an hour, Carpenter said.

The transmitter building is owned by Salem Communications, a national company that provides Christian and family-themed radio programs, including four AM stations in Seattle; KNTS 1680, KKOL 1300, KLFE 1590 and KGNW 820.