Babes in the Wood killer Russell Bishop has died at the age of 55, the Ministry of Justice has said.
The murderer died in hospital from cancer after being rushed there from HMP Frankland in County Durham.
He was found guilty of murdering two nine-year-old girls in a Brighton park in 1986.
He was jailed after being tried for a second time in 2018 using the latest DNA techniques on a sample from the crime scene which yielded a "one-in-a-billion match".
A Prison Service spokesperson said:
"HMP Frankland prisoner Russell Bishop died in hospital on 20 January. The Prisons and Probation Ombudsman has been informed."
Bishop was found guilty of the deaths of Nicola Fellows and Karen Hadaway when new evidence linked him to the crime after he was cleared of their murders in 1987.
The girls were sexually assaulted and strangled in a den in Wild Park, Brighton, more than three decades ago.
A discarded sweatshirt on Bishop's route home linked him to the crime by DNA while fibre, paint and ivy hairs placed it at the murder scene.
Tests revealed a "one-in-a-billion" DNA match to Bishop from a sample taken from Karen's left forearm.
Their mothers described Bishop, who was aged 20 at the time, as an "evil monster" after 32 years of fighting for justice.
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