David McCartney: Drones used in missing walker search

David McCartney was wearing the blue coat pictured above when he was last seen

Drones have been used to scour a swathe of the Yorkshire Dales where a walker went missing four days ago.

David McCartney, 74, failed to return from his hike in the Craven area, near Skipton, on Monday.

North Yorkshire Police said it was "extremely concerned" for his welfare.

Drone searches in the Great Whernside area marked the start of a "significant" effort to find Mr McCartney over the weekend, the force said.

Mr McCartney was last seen leaving his house in Keighley, West Yorkshire, on Monday before heading to the Craven area for a walk expected to last four to five hours.

He was wearing a blue coat, red trousers and an orange and brown scarf and was carrying a red and black rucksack.

North Yorkshire Police said his car had been located by officers in Kettlewell.

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A major multi-agency operation is trying to locate Mr McCartney

The force said two police drones were used to allow them to view aerial footage of vast open areas.

Officers on the ground had been supported by the National Police Air Service helicopter, search dogs, volunteer mountain rescue teams and the RAF.

Insp Martin Smith said the major operation would continue over the weekend.

"I urge anyone who is out walking in the Great Whernside, Kettlewell, Buckden, Grassington and Angram reservoir areas this weekend to be vigilant and to report any immediate sightings of anyone matching David's description to 999," he said.