MARIN COUNTY (CBS SF) — A 35-acre wildfire burning in Samuel P. Taylor State Park in west Marin County is 50 percent contained as of Thursday afternoon, a Marin County Fire Department battalion chief said.

Firefighters used four air drops from fixed-wing aircraft and a helicopter with water from Kent Lake after the fog lifted today to battle the long and narrow fire that is burning brush and grass between the Madrone Group Campground and Mount Barnabe, Battalion Chief Mike Giannini said.

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The eastern entrance to the park is about 13 miles west of downtown San Rafael.

“Things are looking pretty good now as the weather works in the firefighters’ favor. I’m optimistic that crews will be able to strengthen the containment line,” Giannini said early this afternoon.

Marin County Fire had 40 personnel and Cal Fire had about 150 firefighters at the scene, Giannini said.

Land-based equipment at the scene includes nine engines, two water tenders and two bulldozers. Cal Fire brought in crews from the North Bay region and provided mutual aid at Marin County fire stations and other agencies, Giannini said.

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Crews from Woodacre, Hicks Valley and Point Reyes Station responded after the fire was first called in at 4:47 a.m. and the first crew  arrived at 5:01 a.m., according to Giannini.

After daylight, the fire moved slowly toward 1,466-foot Mount Barnabe on the north side of Sir Francis Drake Boulevard, which cuts through the park.

No injuries were reported, no structures were threatened and there were no evacuations in the park, Giannini said. Investigators have not announced a possible source of the fire.

The park remains open but trails are closed and rangers are turning away hikers near the fire.

The blaze is the first significant wildfire of the season for Marin County Fire, Giannini said.

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