Police hunt double murder suspect James Allen, 35, who is being sought in connection with the murders of Julie Davison, 50, of Whitby, and Colin Dunford, 81, of Middlesbrough, Photograph: North Yorkshire Police/PA Police are hunting a 35-year-old suspect after two separate murders in which a man aged 81 and a woman aged 50 were found dead in their homes. More than 100 officers are looking for a suspect named by police as James Allen, following the killings of Colin Dunford in Middlesbrough on Monday and Julie Davison in Whitby, North Yorkshire, on Wednesday. Allen is known to police, and members of the public are urged not to approach him but dial 999. The Cleveland and North Yorkshire police forces issued a joint appeal to find Allen after officers linked the "two brutal murders in the victims' own homes." Earlier, detectives in Whitby said Davison had been found by her sister dead with serious head injuries at her flat. Dunford was found dead at his home in Middlesbrough on Monday. A post-mortem examination showed that serious head injuries had been inflicted in a significant assault. Temporary Detective Chief Superintendent Gordon Lang, head of crime operations for Cleveland police, said: "We now believe the Middlesbrough murder is linked to the murder that took place in Whitby yesterday. Two brutal murders in the victims' own homes. Anyone who can carry out such callous acts needs to be caught as a matter of urgency. We have over 100 officers working on the incident to trace Allen, and we are focusing our efforts in Cleveland and in the Whitby area of North Yorkshire. Anyone who sees him or who knows where he is, we would ask them to contact 999 immediately. Allen is described as 5ft 7in, with a bald head and tattoos on both arms. Earlier, detectives in Whitby had said they did not yet know why Davison was killed. Detective Chief Inspector Kerrin Smith, of North Yorkshire police, said: "This was a brutal murder of a lady who lived on her own, and the motive behind it is unknown at this moment but we are exploring all possibilities. She was found with head injuries serious enough to cause her death. North Yorkshire police said Davison's body was found at 12.40pm yesterday. Officers said that they wanted a man with a dark-coloured mountain bike to come forward. He had been seen near the flats in the square at around 6.30am on Wednesday morning. On Tuesday, police in Middlesbrough said that the man now known to be Dunford had been found dead at his terraced house after he failed to appear at his club. Locals said he had been a daily visitor to the Samuelsons working mans club opposite his home, which was cordoned off and guarded by police. It was believed that when Dunford was not seen at the club, where he often ate his evening meal, members became worried and the police were called. Detectives said there was no sign of forced entry at the house. Dunford was last seen alive at around 5pm on Sunday. Andy Mallett, a member of the club, said earlier this week: "He had not been in last night or the night before, which was out of character for him."