Detectives in Oregon have released a new age-progressed sketch of a 19-year-old woman whose partial skull was found on Mount Hood in 1986 in the hope it might help lead to information on her mysterious disappearance and death a decade earlier.

The drawing by a forensic artist shows what Wanda Herr would have looked like around the time she disappeared in 1976 at 19 years old, Clackamas County sheriff’s officials said Monday.

SKULL FOUND ON MOUNT HOOD IN '86 WAS MISSING 19-YEAR-OLD WOMAN, DNA REVEALS; COLD CASE REOPENED

Detectives were able to confirm last month that the remains belonged to Herr but had only a photo of her at age 12 to work from.

A forensic artist's rendering of Herr around the time she disappeared at age 19, right, and a photo of Herr at age 12, left. (Clackamas County Sheriff’s Office)

The decades-old cold case began on Aug. 2, 1986, when two forestry workers found the skull, bone fragments and a human tooth near the town of Government Camp.

Forensic examiners at the time determined the skull belonged to a woman in her 20s or a small man and that it had been in the woods for around 10 years. Little else was known and the case stagnated for over two decades until a state police forensic anthropologist reexamined the skull in 2008.

The skull was believed to have been in the woods for 10 years before it was discovered. (Clackamas County Sheriff’s Office)

DNA analysis narrowed the description to a female in her late teens to early 20s. A forensic imaging specialist reconstructed the skull with clay, which resulted in a number of tips but no solid leads, authorities said. 

Investigators finally learned the possible identity of the remains last year after a new DNA analysis revealed crucial details that led detectives to a likely name: Wanda Ann Herr, born in 1957.

Detectives interviewed Herr's surviving sisters and determined she disappeared after June 1976 when she was 19. She may have been living in a group home in the Portland suburb of Gresham at the time. 

Herr was raised in a different household than her sisters and was believed to be a chronic runaway, according to the sheriff’s office. There were no records of Herr being listed as missing or a runaway. She also had no DMV record or bank accounts.

Detectives are working to determine what led to Herr's disappearance and death.

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Anyone who knew Herr or has information about her disappearance is asked to contact the Clackamas County Sheriff's Office at (503) 723-4949.

Fox News’ Louis Casiano contributed to this report.