LONDON - An amateur detective claims to have used pioneering DNA technology to prove serial murderer Jack the Ripper was a Polish immigrant. The killer's identity is still a mystery some 126 years after he murdered at least five women and left their mutilated bodies in alleyways across East London. But author and amateur sleuth Russell Edwards says he used DNA from a scarf found near one of the murder scenes to unmask the Ripper as Aaron Kosminski. "I am a hundred percent certain," he told NBC News' U.K. partner ITV News. "Definitive proof, conclusively proven, put the case to bed - we've done this." His theory is detailed in his book "Naming Jack the Ripper," published Tuesday
Edwards worked with Finnish molecular biologist Jari Louhelainen to analyze DNA on a scarf found near the body of Ripper victim Catherine Eddowes. But not everyone is convinced: Richard Cobb, who runs Jack the Ripper tours, told the Times of London that “the shawl has been openly handled by loads of people and been touched, breathed on, spat upon," therefore contaminating the evidence.