The great-great-granddaughter of a police officer who investigated the "Jack the Ripper" murders in 19th century London believes she has uncovered the killer's true identity, the Sunday Telegraph reported.
Sarah Bax Horton has written a book on her research into local cigar-maker Hyam Hyams, who she said closely matches witness descriptions from the time of a suspect seen with the victims.
The "Jack the Ripper" murders, which saw at least six women killed in the East End of London in 1888, remain one of Britain's most notorious unsolved cases.
A whole industry has sprung up around the case, including books, exhibitions and tours around the streets of the Whitechapel district where the women were killed.
Bax Horton said she had identified Hyams, an epileptic and alcoholic who was in an out of mental asylums, as the likely culprit.
Witnesses at the time described a man seen with the victims who was in his mid-30s, with a stiff arm, irregular gait and bent knees.
The author, whose book "One-Armed Jack: Uncovering the Real Jack the Ripper" comes out next month, unearthed medical records for Hyams, who was aged 35 in 1888.
They showed he had an injury that left him unable to bend or extend his left arm, and also dragged his foot and could not straighten his knees.
There were also close similarities in his height and build to the witness descriptions.
Hyams had regular seizures due to epilepsy, the notes, taken from hospitals and asylums, indicated.
He was permanently committed to a mental asylum in September 1889, and died in 1913.
Bax Horton, whose great-great-grandfather was posted at the headquarters of the investigation, concluded that Hyams, who had previously attacked his wife with a "chopper", killed because of his physical and mental decline, worsened by alcoholism.
Hyams' name had been on a "long list" of potential suspects but she said he had "never before been fully explored as a Ripper suspect".
Ripper expert Paul Begg called Bax Horton's findings a "well-researched, well-written, and long-needed book-length examination of a likely suspect".
Agence France-Presse