YAKIMA, Wash. -- An autopsy is scheduled for today for the woman shot in the head early Wednesday on Interstate 82 as the investigation into her death continues.

Sheryl Huntley’s common-law husband says she was shot by a hitchhiker the couple picked up shortly before 3:30 a.m. Wednesday north of Selah.

Detectives announced no major developments in their investigation Thursday.

State evidence technicians started examining the couple’s Dodge Neon about 10:30 a.m. Thursday and were still working in the late afternoon, said Stew Graham, the sheriff’s chief of detectives.

The pair was traveling from their home in Thompson Falls, Mont., to Yakima to return with a niece to Montana, investigators said.

Stephen Harwood, 34, told detectives he struggled with the hitchhiker after the man robbed them. Harwood said the hitchhiker fired several shots, hitting him in the hand and Huntley in the head.

She died after being taken off life support Wednesday afternoon at Yakima Regional Medical and Cardiac Center.

Harwood told detectives his search for a hospital was delayed because he was unfamiliar with the area. He drove down First Street to Union Gap and turned around before flagging down another motorist. That person called 9-1-1, prompting police to stop Harwood’s car at Walnut Avenue.

Graham said detectives have not uncovered any inconsistencies in Harwood’s account, despite the rarity of random homicides in Yakima County.

Barring major developments, the investigation will likely focus on the findings of the evidence team searching the car, Graham said.

Huntley, 40, had lived in Yakima and still has relatives here. She is survived by two sons with a former husband, a sister and her mother.

A memorial service is planned for 12:30 p.m. today at Keith and Keith Ninth Avenue Chapel in Yakima.