COPS are being urged to re-open serial killer Fred West's case over a theory he may have claimed even more victims.

Hollywood screenwriter Paul Pender started investigating the fiend after receiving a tip-off from a man who worked with West’s first wife Rena in a Glasgow abattoir .

He believes more victims may have been buried beneath an allotment site used by West when he lived in Glasgow in the early 1960s.

And the Times reports he says there is now an “inarguable” case for police to act on the shocking new information.

West and his wife Rosemary were arrested in 1994 and accused of murdering 12 people, many at their home in Gloucester where nine bodies were found buried.

The following year the ruthless murderer took his own life behind bars while his evil wife was sentenced to life in prison.

However, the Glasgow allotment is now buried under concrete and would need to be probed with state-of-the-art imaging equipment.

Pender also wants police to interview surviving witnesses about the death of Henry Feeney, a three-year-old who was knocked down by West as he drove an ice cream van in 1965 in the Scottish city.

It was treated as a tragic accident at the time but some locals suspected it was deliberate and was possibly West’s first killing.

Pender, who intends to present his findings at an Edinburgh Festival Fringe show, believes West told the lad there was a ball stuck under a hedge behind the van and when the child went to retrieve it, West reversed over him.

Police Scotland said: “We will investigate all reports regardless of what time has passed and would encourage anyone who has information to come forward.”