Teenagers Maureen Braddy and Allan Whyte were on their way home from a dance at the YMCA Hall in Mundy Street, Bendigo, on the night of Saturday November 23, 1968.

They were reported missing the next day.

It is believed the pair, from Bendigo, met with foul play and it was likely they died the night of the dance. Whyte was aged 17 and Braddy was 16.

Detective Inspector Stephen Dennis believes someone within the Bendigo community holds the key to solving this investigation.

"This disappearance has been extremely devastating to both families who have never given up hope," Inspector Dennis said in a statement on Monday. "We are hoping that today's $1 million announcement will encourage someone out there with crucial information or direct knowledge of this disappearance to come forward."

The reward will be paid at the discretion of the chief police commissioner for information leading to the apprehension and conviction of a person or persons responsible for the abduction and murder.

​In appropriate cases, the Director of Public Prosecutions may consider granting of indemnification from prosecution to any person who provides information.

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