Investigators are trying to determine the cause of a small wildfire that destroyed one outbuilding on the Kootenai National Forest south of Yaak.

The Seventeen Mile Fire had burned about 23 acres as of 6 p.m. on Thursday, according to a Kootenai Forest representative. The fire, which was initially reported Wednesday evening, was burning in timber and blowdowns on a hillside.

It wasn’t known what type of building was destroyed, but firefighters managed to protect other buildings in the area just north of 17 Mile Creek Road. No injuries were reported.

Two hand crews, totaling about 50 firefighters, had dug lines and plans were to establish a hose line Friday. National Forest engine trucks were also on the scene Thursday.

A helicopter dumped water on the blaze and was scheduled to continue Friday.

There were no planned evacuations or road closures as of Friday morning.

Fire danger is rated as moderate on the Kootenai and Flathead forests.

Reporter Scott Shindledecker may be reached at 406-758-4441 or sshindledecker@dailyinterlake.com.