The 'Searching for the Missing' group is to travel to Donegal later this month to conduct a major new search for Lifford man David Coulhoun.
The 21 year old has been missing since May.
He was detained by police in Strabane for a minor incident, escaped and fled towards Lifford. His family believe he entered the River Foyle and drowned.
The Search for the Missing group is made up of volunteers and is affiliated with Abbeyfeale Search and Recovery in Limerick, as well as the Boyne Search and Rescue Service.
Spokesperson Tosh Lavery says over 30 people will travel to Donegal for the search, he is hopeful David will be found: