A 24-year-old Kelseyville man who died in a car crash on a Mendocino County highway wasn't wearing his seat belt and was thrown from his car as it rolled, the CHP reported Tuesday.

Andrew Sampson apparently had been drinking prior to Saturday's crash and CHP officials said officers were investigating whether alcohol may have played a role.

The man crashed at about 4:10 a.m. He rolled his 1997 Honda Accord while driving from Highway 101 outside of Ukiah onto Highway 20, the CHP said.

When the car moved onto the left shoulder, he tried to correct and lost control. The Honda overturned and landed on its roof in a drainage ditch.

Sampson was flown to Santa Rosa Memorial Hospital. He was declared dead at 6:20 a.m. according to Sonoma County Coroner's reports.