Officers are appealing to the public for information about a man who has been missing for several days.
Ian Malone, 52, was last seen in the Low Fell area at around 8am on Friday, April 7.
However, he has not been heard from since and police are now growing increasingly concerned for his welfare.
A force spokesperson said: "Searches have been ongoing to locate Ian and ensure that he is safe and well – and we are now asking anybody who thinks they may have seen him to get in touch.
"Officers understand that Ian could have been heading to the Hadrian’s Wall and Pennine Way areas of Northumberland.
"Ian is described as a white male of medium build, around 5ft11 in height, with a bald head. He is usually clean shaven, but sometimes has a goatee beard.
"Ian is believed to be wearing black jogger bottoms, with a blue jumper and black gilet. He also often wears glasses.
"Ian, or anyone who has seen him, is asked to call 101 immediately quoting log NP-20230407-1045."
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