Fears are growing for a Nuneaton man who has been missing since Monday morning.
Mr Mason went missing just after arriving at work at approx 0930hrs on Monday leaving his mobile phone and keys in his car.
It is understood that he is an Armed Forces Veteran.
Police and concerned friends and family have been searching for Robert and volunteers are being asked to join their numbers.
Volunteers are being asked to prepare a bag including water, food, sun cream, jacket, torch, notebook, pen and hi-vis vest.
Robert was believed to have been wearing a dark fleece, dark trousers and carrying a rucksack when he went missing.
He has been described as white, 5ft 8in tall, slim, with dark hair and brown eyes.
Anyone who sees Robert or has any information on his whereabouts is asked to call Warwickshire Police on 101 or contact Crimestoppers anonymously on 0800 555 111 or visit