Police are investigating a diesel raid on a County Durham farm that has left one woman dead and her son badly hurt.

Police said William Dove and his wife Rosemary were returning to their home at East House Farm, Bishop Middleham, Co Durham, when a man was spotted by the couple trying to steal diesel from a pump.

Mr Dove went to confront the intruder while his wife went inside the house to phone 999 and alert relatives who live on a nearby farm.

Mrs Dove, 68, then complained of feeling unwell and collapsed on the floor of the farm where she was later pronounced dead by paramedics.

Mr Dove meanwhile had been joined by his son James and other relatives who chased the intruder's silver Mitsubishi-style pick-up truck, which sported a distinctive amber lighting bar on the roof, across the fields in their own vehicles.

After cornering it in a field, James approached the intruder's vehicle but was clipped as the pick-up truck attempted to escape. He is being treated for a double hip fracture and a minor head wound.

Durham Constabulary's Detective Chief Inspector Paul Harker, who is leading the investigation, has appealed to the public for help, saying: "At this stage it is not clear exactly how many people were in the pick-up.

"We urgently need any help that will lead us to those involved in this tragic series of events that has left the Dove family absolutely devastated."

The intruder is described as white, of muscular build with short dark brown hair and aged between 20 and 30 and wearing a check-style shirt.

Anyone with information is asked to ring the police non-emergency number on 0845-6060365 or anonymously to Crimestoppers 0800 555111.

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