Melbourne murder case appeal renewed 25 years after woman vanished

A quarter of a century after 23-year-old Sarah MacDiarmid failed to return to her home in Melbourne's south police are renewing their appeal for information on her suspected murder.

She was last seen walking through the car park of the Kananook Railway Station near her Frankston home at about 10.20pm on July 11, 1990.

Forensic testing of the area where her car was parked at Kananook station led detectives to believe Ms MacDiarmid was murdered.

Cold Case Detective Leading Senior Constable Mark Berens said on Saturday that someone in the community knew about the murder and he urged them to come forward to help bring closure to the MacDiarmid family.

A $1 million reward, first offered in February 2004, is still available for information leading to a conviction.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000.