Bones found in the San Francisco bay area are those of a Swedish exchange student who disappeared more than 30 years ago, authorities said on Monday.

The US Department of Justice matched seven bones discovered in a canyon in Fremont five years ago to Elisabeth Martinsson, 21, who was going to the College of Marin and living with a family in nearby Greenbrae when she disappeared on 17 January 1982, coroner’s officials said.

Federal officials used dental records to identify the remains in November, Alameda County sheriff’s sergeant Patricia Wilson, an investigator in the coroner’s division, told the Marin Independent-Journal.

No cause of death was determined, Wilson said, and Martinsson’s remains were cremated and will be sent to her family in Uddevalla, a Swedish town about 50 miles from the Norwegian border.

It wasn’t immediately clear why the information was released now instead of last year when the remains were identified.

Martinsson disappeared after going to a store in the Volkswagen Rabbit she borrowed from the family she was living with.

Ten days later, a 31-year-old convicted rapist was found with the car in Oklahoma. The man, Henry Coleman of Los Angeles, was wanted on a robbery warrant out of California. He was convicted of auto theft and sentenced to five years in prison, but was never charged with Martinsson’s death.

Coleman told investigators he had bought the car from a man he met at a bar in San Francisco.

Marin County sheriff’s officials and Fremont police are collaborating on how to proceed with the case and have requested more tests from the Department of Justice, sheriff’s lieutenant Jamie Scardina said.

