A northern Arizona sheriff’s office says human remains found in a dry creek bed near Interstate 17 on New Year’s Day are those of a missing California man.

The Yavapai County Sheriff’s Office on Friday said the county medical examiner identified the remains as those of 31-year-old Shane Rollman. His car had been found abandoned about two miles away at a highway rest area on Sept. 23. An extensive search of the area at the time found no sign of Rollman.

The West Covina police department had issued a missing persons bulletin 10 days before his car was found by Arizona state troopers. Sheriff’s spokesman Dwight D’Evelyn confirmed Rollman was from the city of West Covina, and an FBI missing persons bulletin said he has lived in that city.

The sheriff’s office said in a news release that the cause and manner of Rollman’s death has not yet been determined.