SONOMA COUNTY (CBS SF) – A driver was killed in a solo crash along Highway 116 in Sonoma County late Sunday night.

Around 10 p.m., a passerby on the highway at Guerneville Road west of Santa Rosa spotted a Volvo wagon off the side of the roadway. When officers with the Santa Rosa office of the California Highway Patrol and firefighters arrived, they found the driver unresponsive in his seat.

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The driver was pronounced dead at the scene.

According to a preliminary investigation, the Volvo was traveling westbound on Guerneville Road when the vehicle went through the stop sign and crossed the highway, where it struck an embankment and a tree.

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Officers said it appeared the driver was not wearing a seat belt at the time of the collision. No further details about the crash were immediately available.

The driver’s name has not been released by authorities.

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Anyone with information about the crash is asked to contact the Santa Rosa CHP office at 707-588-1400.