WINDSOR (CBS SF) — At least one person died Sunday morning in unincorporated Sonoma County after their vehicle struck a tree.

At 4:34 a.m., the California Highway Patrol first learned of the crash, which happened near 9450 Eastside Road, near Windsor, according to the CHP.

A person who was driving in the area around the time of the crash stopped and said the victim was inside the vehicle and was unresponsive, CHP officials said.

CHP officials are investigating the crash.

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