The chilling echoes between the Ripper attacks and the killings of Jacci and Barbara

Did Peter Sutcliffe have 'secret victims' he was never convicted of killing? And did they include two young hitchhikers? It's a chilling theory which Manchester Evening News chief reporter, Neal Keeling, explores here, in the last of a series of special reports, the first of which looked in detail at the case of Jacci Ansell-Lamb, and the second of which told the story of Barbara Mayo.

Former police intelligence officer, Chris Clark, is convinced two young women hitchhikers were murdered by the same man. He believes they are among many 'secret' victims of Peter Sutcliffe, the Yorkshire Ripper.

The body of Jacci Ansell-Lamb, 18, was found in a copse near Square Wood, at Mere, Cheshire, on the morning of March 14h 1970. After going to a party in the capital she had set off from Hendon in London to thumb a lift back to her new attic flat in Manchester on March 8th.

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Seven months later, on October 18th, the body of Barbara Mayo, 24, was discovered in a wood at Ault Hucknall, near Chesterfield. She had been trying to hitchhike from Hendon to Catterick to pick up a car from a garage.

Both women had been raped and strangled. Both were found in secluded rural locations, near to motorways. Both had suffered wounds to the head.

Chris believes the geography attached to Sutcliffe's private life at the time, and the way in which both were killed, and how the crime scenes were left, point to him as being responsible.

By the time of Jacci's murder Sutcliffe’s relationship with his future wife Sonia Szurma had become serious. Sutcliffe would often accompany Sonia when she attended her music graduate sister