Alma Johnston acknowledged the force in a notice in the Evening News even though the police searched for two months before Mr Goulden's dead body was discovered in his own garden.

Alan Goulden, 64, disappeared from his home in Edinburgh in August but despite a nationwide search including diving teams, horse patrols and sniffer dogs, no trace of him was found.

But a local pest controller found the man's body in a bush just feet from Mr Goulden's front door earlier this month.

In a public notice she wrote: "(I) would like to thank Graham, Martin and Susan and families for their support over this difficult time, and to all friends and colleagues who attended Alan's celebration service.

"To Rev Stewart McPherson, William Purves and Lothian and Borders Police, I extend my sincere gratitude and thanks."

Shortly before the find Lothian and Borders Police announced they were stepping up efforts to look for the former RAF serviceman whose son is a high ranking officer in the force.

The search for Mr Goulden was one of the force's largest missing person operations. During the time he was missing a full page advert was taken out in a national newspaper.

On September 9 – more than a week after he vanished – police trawled the River Almond and searched Cramond Island for clues. After four weeks and no fresh information on Mr Goulden's whereabouts police set up roadside checks at a bus stop in Corstorphine to question members of the public.

Strathclyde Police have been called in to investigate the search and the procedures used by Lothian and Borders Police.

Senior police officers previously said they had the "steadfast" support of Mr Goulden's family.