Serial killer and rapist Angus Sinclair has died in prison, aged 73.
He was imprisoned in HMP Glenochil in Scotland.
The Scottish Prison Service confirmed his death to The Independent.
Sinclair was convicted of the notorious World’s End murders in Scotland.
He had spent more than half his life behind bars for killing four girls as well as for a string of sex attacks on young children.
Detectives suspect Sinclair could have been behind several unsolved murders from the 1970s.
An inquiry will be held “in due course”, the prison service said.
Sinclair was sentenced to life in prison in 2014 for raping two teenage girls before strangling them to death with their own underwear after his second trial for the World’s End murders, named after the Edinburgh pub in which the two victims were last seen alive.
The murder of Christine Eadie and Helen Scott, both 17, in October 1977, become one of Scotland’s highest-profile unsolved crimes for nearly four decades.
Sinclair was put on trial in 2007 but formally acquitted after a judge ruled there was insufficient evidence to prosecute.
He was later convicted under Scotland’s double jeopardy law, which allowed him to be retried.
A jury took less than two-and-a-half hours to convict Sinclair unanimously of both charges following a five week trial.
The serial rapist had already spent more than 30 years in prison at the time.
Sinclair was just 16 when he strangled eight-year-old Catherine Reehill to death in Glasgow in 1961.
He later plead guilty to a charge of culpable homicide, the Scottish equivalent of manslaughter, and served only six years in prison.
In 1982, he was convicted at the High Court in Edinburgh for a string of sex attacks on 11 young children, including three rapes.
While still in prison, he was given a life sentence in 2001 for the murder of 17-year-old Mary Gallacher, who was raped and stabbed in Glasgow in 1978, a year after the World’s End murders.
