An anonymous letter could offer a huge break in the 10-year-old case

Gardaí has begun to excavate a Donegal beach in search of the body of Dr. Deirdre O’Flaherty (nee Donnelly), who went missing in January 2009.

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Sources say that an anonymous letter prompted Gardaí to reopen their search for the missing mother-of-three, despite a Belfast High Court ruling in 2012 that O’Flaherty was presumed dead.

In 2009, O’Flaherty, a GP based in Strabane, Co Tyrone, was on holidays in Moville, Inishowen, Donegal with her family when she went missing. Her abandoned car was recovered at Kinnego Beach, but her body was never found.

The Irish News and report that the excavation was prompted by an anonymous letter regarding the whereabouts of O’Flaherty’s body.

A garda spokesman said: "An Garda Síochána in County Donegal have commenced a land search and excavation in the Milford District. The search forms part of a missing person investigation.”

"An Garda Síochána are liaising closely with the relevant family and a Garda family liaison officer has been appointed.”

"The search will be carried out by members of the Donegal Divisional Search Team and Garda Technical Bureau along with private contractors and is expected to last up to 5 days.”

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"This development continues to form part of a Missing Person investigation and there is no change of status regarding same.”

"An update will be provided when the search is completed."

The family of Dr. Deirdre O'Flaherty has requested that their privacy be respected at this time.