LAKESHORE, Ont. - Police say they have new DNA evidence that may help them solve a cold case murder that dates back 33 years.

Russell Floyd Cook, 29, known as "Rocky" was found shot to death in a ditch on South Middle road in what is now the town of Lakeshore, near Windsor.

Two years ago, police reopened the 1977 case after receiving new information. They also and offered a $50,000 reward.

At the time police refused to describe the nature or source of the new details.

On Friday, police did not specify where the new DNA evidence came from.

They said the new evidence as well as statements gathered across North America will move the investigation forward.

Police say they believe Cook, who worked as an ambulance attendant, was robbed and then murdered.