Joseph Colhoun has broken his silence to speak through donegaldaily to ask for anyone who has diving experience to join the search for the missing 22 year old.
David, from Beechwood Grove, was last seen in the early hours of Sunday morning last in Strabane near the River Mourne.
He had been in PSNI custody for a minor offence when he escaped and headed towards the river.
Tragically he has not been seen since and his family fear he may have drowned.
Speaking through a third party Mr Colhoun said “We just want David back and we are appealing to anyone with diving experience – diving clubs or individual divers to help us.
“We are at our wits end and we would be so grateful if people could help join the search especially divers.”
The area where David went missing is the responsibility of the PSNI but they say they cannot put divers into the water until Friday because of operational difficulties.
Gardai have been in the area on the south side of the river and an RNLI search and rescue helicopter was also in the area yesterday.
Mr Colhoun and his three children as well as David’s girlfriend Nicola McConnell have been distraught since his disappearance on Sunday.
Anybody who can provide any assistance including diving help can contact 086 3868538.
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