Specialist police search teams are continuing to focus on a riverside footpath where a former solicitor was found with fatal stab wounds.
Peter Maine, 56, from Wynyard, was found on a footpath opposite the running track at Maiden Castle sports centre, on the outskirts of Durham City, just after 8am on Sunday, September 1.
He was found to have three wounds to his chest and was confirmed dead shortly after being taken to the University Hospital of North Durham.
Police are continuing to treat his death as suspicious and unexplained, but stress they are keeping an open mind as to how he received his injuries.
Since last Sunday up to 30 officers at any one time have been combing the fields and undergrowth in the area where Mr Maine was discovered by a passing cyclist.
Officers from Northumbria Police’s marine unit have also made several trawls of the river in the same area, and on Thursday a crew from County Durham and Darlington Fire and Rescue used a specialist underwater camera to check the riverbed.
The marine unit and the fire and rescue crew will help with the searches again today and over the weekend.
Detective Chief Inspector Steve Chapman, leading the investigation, said they were following up numerous potential leads and had traced a number of people who had been in the area over the weekend of August 31 and September 1.
He said: “We have traced or been contacted directly by around two dozen people, a mixture mainly of campers, cyclists, dog walkers and joggers.
“Their accounts are proving very useful as we try to establish exactly what happened to Peter in the 20 minutes from when he set out running to the time he was found.
“His family and friends describe him as a popular man who loved his music and was a regular at his local gym as well as being a keen runner.
“If there is anyone else who was in Durham city on Sunday morning, especially anyone who was in the riverside area between Baths Bridge and Maiden Castle I would urge them to come forward,” he said.
Anyone with information should contact the incident room at Durham Police headquarters on 101 or call Crimestoppers on 0800 555111.