A man convicted of killing a Cheltenham barmaid has died after collapsing at a secure psychiatric hospital.
Paul McMillan, 27, stabbed Shirley Cotton-Betteridge more than 40 times at a Bristol pub in 2001.
He punched and kicked her to the ground as she was cashing up, before stabbing her to death in a frenzied attack.
McMillan pleaded guilty to manslaughter and was given a life sentence. On Thursday he was found unconscious at Broadmoor and later died in hospital.
A spokesman for the West London Mental Health Trust confirmed an investigation had been launched.
A year before the fatal stabbing, McMillan had been released from a young offender institution - while still considered to be a risk - after serving a sentence for indecently assaulting a girl and causing her grievous bodily harm.
He pleaded guilty to the killing in October 2002.