DETECTIVES are treating as "murder" the death of a 78-year-old bogus caller victim. An attempt to swindle cash from David Wardlaw and his wife went horribly wrong when he collapsed and died on his front lawn in Northfleet.

Supt Dave Ainsworth, head of North Kent police, said detectives were treating the tragedy as a "moral murder inquiry". He said the search was on the scale of a murder investigation.

Mr Wardlaw, of Struttons Avenue, Northfleet, became suspicious of a caller, who said he was from the water authority, and asked to take a picture of him. His wife Betty, 74, went to get a camera and met two men coming downstairs. She found both bedrooms had been searched and £200 was missing. When she went downstairs all three men had left and her husband was lying in the front garden.

Det Chief Insp Brian Roberts, in charge of the investigation, said that although the cause of death was a heart attack the seriousness of the crime should not be belittled.

He said: "Had it not been for the actions of the three offenders, Mr Wardlaw would almost certainly have been alive today."

Anyone who saw an M registration silver Vauxhall Cavalier parked in Harden Road, or any other information, should telephone Dartford police on 01322 283147 or Crimestoppers on 0800 555111.