A POLICE force is trying to solve a mystery surrounding one of its own.

The curious case of Constable X centres on a 65-year-old photograph of officers at Stanhope, in Weardale, County Durham.

An inscription on the photograph reads: "Presented to Chief Inspector P Storey by members of the Stanhope Division on his retirement from the Durham County Constabulary, 8th January, 1935".

The names of all 17 members of the force at that time, one chief inspector, four sergeants and 12 constables, have all been carefully written on the back of the photo - except one.

After close scrutiny, it has emerged that the picture of Constable X was inserted in the original photo and touched up at a later date.

Divsional police commander Superintendent John Curry said: "It's certainly a bit of a mystery.

"We are not so concerned about the name of the unidentified constable on the photograph, but why he was so obviously substituted at a later date?"

Among theories being advanced are that he may have been ill, on leave or even suspended from duty when the photo was taken.

Plans are afoot to refurbish the police station at Stanhope, built in the mid-1800s, and Supt Curry is hopeful the mystery surrounding the 1935 photo can be solved so it can be displayed as part of the history of policing in Weardale.

Clues to the identity of Constable X or why his picture was inserted in the photo at a later date should be sent to Sergeant Jim Pitcher at either Stanhope or Crook police stations.