A Sonoma County woman was hospitalized after she attempted to commit suicide by setting herself on fire late Tuesday night in rural Bennett Valley, authorities said.

The woman, whose name was not released, said she had taken two Xanax and poured gasoline on herself, said Rob Thompson, a former volunteer firefighter who found the woman, naked and badly burned, wandering in a ditch off rural Sonoma Mountain Road.

Investigators believe she was trying to commit suicide when she set herself on fire in the 4000 block of Sonoma Mountain Road, sheriff's Sgt. Carlos Basurto said.

The woman suffered second-degree burns from her waist up, and on her face, arms and hands, firefighters said. Thompson said he also observed burns on her legs.

She was taken to Santa Rosa Memorial Hospital by ambulance, and later transferred to Saint Francis Burn Center in San Francisco. Her condition was not available Wednesday.