A specialist search team has been called in as the hunt for a missing Hartlepool man focuses on a former industrial site.
Darren Waller, 36, was last seen in the town on 9 January and a number of searches have already been carried out.
On Saturday, the former Steetley site, which Mr Waller had been known to walk his dog past, will be searched.
Volunteers from Cleveland Search and Rescue Team will join police officers at the former chemical works.
Det Supt Gordon Lang, from Cleveland Police, said: "We have searched numerous locations as part of our inquiries, around Hartlepool and the surrounding areas, and are becoming ever more concerned about Darren's whereabouts.
"Darren walked his dog around the area where the site is and we feel that it may be a significant place to search next."
Mr Waller is originally from the Headland, Hartlepool, and was last seen in the Foggy Furze area of the town.
He is 5ft 8in, white, with a shaved head and tattoos on his hands and arms and an earring in his left ear.