'Difficult to prevent' Cerys Yemm murder in Argoed
It would have been difficult for mental health services to predict or prevent the killing of a 22-year-old woman in Caerphilly county, a review has said.
Matthew Williams, 34, killed Cerys Yemm at a hotel used to accommodate ex-offenders in Argoed in November 2014.
He died after being tasered by police on the night of the killing.
Williams had a criminal history and had been placed at the Sirhowy Arms Hotel after being released from prison two weeks earlier.
Healthcare Inspectorate Wales (HIW) found he had been a drug user for years. It said he was likely to have had a severe reaction to "psychoactive substances" he took.
The report said he had been offered support to address his addiction after being released from prison, but had not been willing to take up that help.
It added although Williams had shown signs of a "low mood" in the days before the attack, there had been no sign of psychosis or schizophrenia.
HIW said his change in behaviour was likely to be as a result of his taking of "illicit or psychoactive substances".
'Only victim was Cerys'
In a statement Ms Yemm's family, from Blackwood, said: "We as a family welcome that the independent investigation and report carried out by the HIW has finally come to a conclusion.
"The only victim in this case was Cerys. A fact we feel has been lost."
A statement from Williams's family said: "At this stage the family will not be commenting on the detail of the report other than to confirm that they do not agree with the content of the report in its entirety.
"The family have concerns over the lack of information provided to HIW and have identified a number of inaccuracies within the report."
The report makes recommendations to improve healthcare and support including better sharing of information, but stressed none of those issues contributed to the death of Cerys Yemm.