A killer was experiencing a psychotic episode brought on by his use of cannabis and amphetamine when he brutally killed and mutilated a "beautiful and caring" young woman, an inquest jury has found.
Jurors said Matthew Williams, 34, who suffered a cardiac arrest shortly after being tasered by police officers responding to a 999 call, died a "sudden, unexpected" death caused through a "culmination of illicit drug use and struggle against restraint", Gwent Coroner’s Court heard.
On Wednesday, the jury found that Cerys Yemm, 22, who was attacked by Williams in his first floor room at the Sirhowy Arms Hotel, Argoed, South Wales, at around 1am on November 6 2014, was killed unlawfully by him.
Williams used the broken shards of a cereal bowl to cut her face and neck, removed one of her eyes and bit her stomach, the inquest heard.
Miss Yemm’s screams alerted other residents and hotel owner Mandy Miles opened door to the room to find the "horrific" scene of Williams, who had a history of drug use and mental health problems, on top of her with blood dripping from his mouth.
Williams carried on with his grisly attack despite the interruption, snarling "that is no girl" when he was asked what he was doing to Miss Yemm.
In relation to his death jurors said: "In the early hours of November 6, 2014, Matthew Williams was in his room at the Sirhowy Arms Hotel.
"Prior to his death Matthew took amphetamine and cannabis which led him to experience drug-induced psychosis."
They said the drug use "caused him to become violent" and added: "After the subsequent arrival of the police Matthew was restrained and he resisted arrest.
"He was attended by paramedics but his condition deteriorated and he was transferred to an ambulance (where) attempts were made to resuscitate him.
"Matthew was pronounced dead at 02.18 hours."
In his summing up, Coroner David T Bowen told jurors the only finding they could make in respect of Miss Yemm’s death was of unlawful killing.
In respect of the circumstances of her death, the jury said: "In the early hours of November 6 2014, Cerys Yemm was with a companion in his room at the Sirhowy Arms Hotel when she was violently attacked and she suffered severe and fatal injuries."
Mr Bowen directed the jury to return a narrative finding in respect of Williams and said he did not require them to make any findings of fact in relation to the wider circumstances.
In a statement released following the conclusion of the inquest, Miss Yemm’s family said: "We want to pay tribute to our beautiful daughter Cerys, who was kind, caring and could always see the best in people."
They said Miss Yemm was killed while Williams was in a psychotic state through illegal drug abuse.
"Throughout this inquest we have been searching for the answers to our questions as to how her murder, which has so devastated our family, could take place in the heart of our community and why the agencies responsible for protecting the public from violent offenders could not prevent this awful event from occurring."
The family of Williams have said evidence heard during the inquest had exposed "clear failings" in the mental health, housing and criminal justice system.
In a statement read out on behalf of the family, they said: "We regret that the jury were not given the opportunity by the coroner to express their view on these issues.
"We hope that this case will highlight the need for better mental health care and lead to the effective sharing of information between state agencies and that another family will not have to go through what families touched by this inquest have had to endure."
The family said they would like to repeat their "sincere condolences" to Miss Yemm’s family and added it had been agreed allegations of cannibalism, published in the press after the incident, were unfounded.
They said: "In participating in this inquest we have not sought to excuse our son’s actions but have tried to understand them.
"Matthew was a very troubled man with significant mental health difficulties made worse by drug abuse.
"He had needed long-term support and treatment for many years but this was not available either in prison or in the community.
"We were also surprised that the health board, Abertawe Bro Morgannwg chose to play no part in this process."