A West Yorkshire police chief has criticised a former detective for claiming the Yorkshire Ripper Peter Sutcliffe could be responsible for a string of unsolved murders around the country.

Retired policeman Chris Clark, 68, a former intelligence officer with Norfolk Police, has been carrying out research for 18 months and says he has evidence to suggest that the Bradford lorry driver committed a further 17 murders.

He is now appealing for information about three historic Bradford attacks, in which the women victims survived, which he believes might also be linked to Sutcliffe.

But West Yorkshire’s most senior detective, Detective Chief Superintendent Andy Brennan, has insisted Mr Clark has provided no new evidence to back up his claims.

Mr Clark has admitted his evidence is circumstantial. But he said: “I was looking at unsolved murders and when I compared those victims with the methods used by the Ripper, the nature of his attacks and how he selected his victims, there were several features indicative of what he was doing from 1975.”

Most of the unsolved cases took place around London, Essex and the Midlands, but they include the murder of Bradford woman Carol Wilkinson.

Miss Wilkinson, 20, was bludgeoned to death with a coping stone as she walked to work near to the Ravenscliffe estate in October 1977, in a killing which bore similarities to that of known Ripper victim Yvonne Pearson.

Anthony Steel spent 20 years in jail for the murder, but his conviction was quashed in 2003. He died four years later. Mr Steel’s family, and Sutcliffe biographer David Yallop, also believed Miss Wilkinson was a victim of the Ripper.

Sutcliffe, now in his 60s, is serving a whole life sentence for the murders of 13 women and attempted murder of seven others and has been held at top psychiatric hospital Broadmoor since 1983.

Now Mr Clark, of Crook, County Durham, is focusing on three attacks in Bradford in the 1970s where women victims survived.

He said: “In two of the cases the descriptions of the attacker are very similar to Sutcliffe, and in the third the method of attack is the same. I am looking to see if they connect with the ones I am already looking at. I would be happy to receive any information about these attacks.”

They include an attack on 18-year-old Rosemary Stead, in Queensbury in January 1976. The teenager was walking home from work when she was attacked in a snicket off Halifax Road, battered over the head with a blunt instrument and left unconscious and in a pool of blood. She managed to stagger home and raise the alarm.

A second attack, in August of the same year, involved the stabbing of mother-of-four Maureen Hogan, 39. She was found laid in a shop doorway in Listerhills.

Mr Clark said the third incident occurred in November 1978 when an 18-year-old woman was attacked by a man matching the description of Sutcliffe. She was grabbed by the hair and there was a struggle but the man ran off when she threw a brick at him.

Det. Chief Supt. Brennan said: “Peter Sutcliffe was convicted of 13 murders and seven attempted murders in 1981.

“West Yorkshire Police regularly reviews evidence from this case and all other unidentified murders in light of new information and advances in forensic science.

“Senior detectives have recently met Mr Clark and he has provided no new evidence to support his claims.

“It is a very significant step to start making such claims and Mr Clark was strongly reminded of his responsibilities in managing the expectations of relatives still grieving for murdered loved ones.”

Responding to Det Chief Supt Brennan’s comments, Mr Clark said: “I have no responsibility other than a public sense of duty to bring closure for the loved ones left behind. I met a detective chief inspector from West Yorkshire Police last October after I submitted a request under the Freedom of Information Act for extracts from a Ripper report to be released to me.

“I had a dossier of evidence but they did not ask for it.” He added: “I want to be clear I am not questioning the credibility of West Yorkshire Police.”