Police are continuing to investigate the death of a solicitor from Stockton-on-Tees who had gone out jogging.
56-year-old Peter Thomas Maine, from Wynyard, was found with stab wounds near the running track of the Maiden Castle Sports Centre in Durham.
He was discovered just before 8am on Sunday.
Durham Constabulary said 30 detectives and staff are now working on the case and are keen to speak to anyone who saw Mr Maine that morning.
It emerged that Mr Maine was under investigation for fraud by Durham Police in connection with his job as a lawyer.
The Solicitors Regulation Authority had also launched an investigation into his conduct.
The police are distributing posters with a picture of Mr Maine in the hope it will prompt potential witnesses to come forward.
"Mr Maine's death remains suspicious but we have to keep an open mind as to how he came by his injuries.
"We have established a major incident room at police headquarters and we are committing the same resources we would for any homicide investigation."
More top news
Flying Scotsman travelled alongside three modern trains to celebrate the "past, present and future" of Britain's railway this morning.
Rain develops overnight into Monday before colder and stronger air digs in from the north - bringing the risk of snow, frost and ice
Results for other teams on Saturday means Newcastle United will be promoted to the Premier League on Monday if they beat Preston North End.