NEAR OLYMPIA - Investigators are looking for a person who they say deliberately set fire to a tree plantation inside Capitol Forest in Thurston County.

A spokesperson for the Washington State Department of Natural Resouces says someone lit an "incendiary device" in a pile of brush. The fire spread to about 12 acres of land that had been harvested a couple of years ago and had been replanted.

The brush fire broke out Friday inside Capitol Forest about 20 miles west of Olympia. Three helicopters with wate scoop buckets worked on the fire Friday.

The helicopters scooped water from a nearby lake to try to douse the flames. Crews also used a bulldozer to try to keep the flames contained.

The fire has now been contained. No aircraft will be launched to fight the fire Saturday, but pilots are on standby, if needed. Hand crews will work on keeping the fire within the current fire lines and move to the middle of the area.

None of the flames have reached tall timber. The fire is close to the Fall Creek Campground.

A voluntary evacuation was in effect Friday night, but no homes or buildings were damaged.