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Ex-deputy police chief says search challenging
Gareth Pritchard, former deputy chief constable of North Wales Police and trustee of the Ogwen Montain Rescue Team charity, says locating the teenagers is the biggest challenge facing the emergency services.Speaking on BBC Radio Cymru's Dros Ginio programme, he said: "It is such a vast area and not knowing the route of the teenagers will make it even more challenging and will take a lot of time."
He says the community's knowledge and help is essential in the attempts to locate the the teenagers.