The possible sighting of Black is being reinvestigated

Black is serving a life sentence in England for the murder of three girls, including Caroline Hogg in Edinburgh and Susan Maxwell in the Borders.

Police are now checking evidence of a key witness which could link Black to the death of 16-year-old Pamela Hastie.

A van driver claims a man he hit on the night she died in 1981 was Black.

Miss Hastie was sexually assaulted and murdered in Rannoch Woods in Johnstone.

Case review

The following year, a local man, Raymond Gilmour was convicted of raping and murdering her but he is now on bail pending an appeal.

The Scottish Criminal Cases Review Commission (SCCRC) criticised a lack of evidence and doubted the reliability of his confession.

It said: "The lack of forensic evidence cast doubt on the reliability of the confession without which there would not have been sufficient evidence to convict Mr Gilmour."

Pamela Hastie's body was found in Rannoch Woods

It has now emerged that a van driver reported to police he had hit a man on the night of Pamela's death.

The van driver later identified the man as Robert Black when he saw a picture of him 13 years later.

Police hunting Pamela's killer disregarded his evidence, but Lothian and Borders Police detectives working on the continuing inquiry into Black are reinvestigating.

Although Black was convicted of three murders and one attempted abduction, it is widely believed that he killed more girls.

Les Brown, from campaigning group A Search for Justice, said: "If it wasn't Robert Black then who the hell was it?

"I've always said this, who was this man that collided with this van? This van driver is in absolutely no doubt that the man that he collided with in the vicinity of Rannoch Woods was a man who was running from something."