The CHP is investigating the death of a driver whose truck fell down a 90-foot cliff and caught fire early Monday near North Salmon Creek Beach.

A passerby reported the solo crash at about 12:40 a.m., CHP Officer William Brown said. Only one person was in the fully engulfed 2008 GMC truck, which rolled off the west side of the road, he said.

Two firefighters went down to the beach on foot to scope out the crash site to see how serious it was and if there was anyone they could help, Bodega Bay Fire Capt. Dave Bynum said.

“From the beach level you could tell that the car had been burning for a while and there was one occupant inside that was deceased,” he said.

Authorities could not say whether the driver was a man or a woman.

The tide was in, and waves were hitting the truck when the firefighters arrived, Bynum said. The truck was upside, its tires burned off and the interior of the vehicle gutted by the flames, he said.

Firefighters opted to extinguish the fire from the roadway above, preserving as much evidence from the crash, Bynum said.

Both lanes of Highway 1 were shut down for almost two hours as a tow truck pulled the vehicle up the side of the cliff. The highway reopened at about 7:30 a.m.

CHP officers remained at the site for several hours. They had not determined what direction the truck was going or how it rolled off the cliff, Brown said.

You can reach Staff Writer Nashelly Chavez at 707-521-5203 or nashelly.chavez@pressdemocrat.com. On Twitter @nashellytweets.