The Government is to examine whether a man reported to have murdered a woman in an act of cannibalism was properly managed following his release from prison.
Cerys Marie Yemm, 22, died from her injuries at Sirhowy Arms Hotel, a homeless hostel in Argoed, Blackwood, south Wales, in the early hours of Thursday morning.
Her attacker, Matthew Williams, 34, who had recently been released from prison, also died at the scene shortly after police discharged a 50,000-volt Taser and arrested him.
South Wales Police launched a murder investigation after the deaths and the Independent Police Complaints Commission (IPCC) will also probe the incident.
Today, a spokesman for the Ministry of Justice confirmed a serious further offence review will take place to see if lessons can be learned from the case.
Such reviews are immediately launched if a serious offence is alleged to have happened within 30 days of a person leaving prison or is on licence.
The review will examine the circumstances of Miss Yemm's death, the management of Williams following his release and whether steps can be taken to improve public protection.
Welsh Assembly member William Graham has led calls for an inquiry into reports Williams was not monitored upon his release from prison.
"It is now clear that Mr Williams posed a risk to the public and I am extremely concerned that monitoring appears to have been deemed unnecessary," Mr Graham told the BBC.
"If true, a wider inquiry into the circumstances surrounding his release is urgently required."
Thousands of people have joined tribute sites to Miss Yemm, a shop worker, but some Facebook pages have been hijacked by internet trolls.
One page, Cerys Marie Yemm, listed as a "community", directs mourners to a video with the comment: "Video Tribute in Memory of Cerys Yemm. Rest in peace pretty girl."
However, grieving friends who click on the video are instead taken to pornographic material, with some complaining they are being asked to pay £24 to view it.
The scam is repeated on another page, a "community" named Cerys Yemm, which has more than 3,000 "likes" by Facebook users.
Nicola Chadwick wrote: "Who ever posted this video is as sick as the man who committed the hideous crime against this beautiful young girl, I've reported this video.
"I hope your found and prosecuted. You should be f****** ashamed."
Shelley Davis posted: "I've tried the video and I'm getting porn whoever did this is a nasty sick saddo."
Gwent Police said Williams became unresponsive while under arrest and officers and paramedics administered first aid but he was pronounced dead.
A post-mortem was due to be carried out on Williams, a resident of the Sirhowy Arms Hotel, yesterday, a spokesman for the IPCC said.
Miss Yemm's death is being treated as murder and police are not looking for anyone else. Her family, and officers who attended the incident, are being supported by specialist officers.
Detectives have refused to comment on the specifics of the tragedy but sources confirmed Miss Yemm suffered substantial facial injuries.
Chief Inspector Paul Staniforth of Gwent Police told reporters yesterday: " The post-mortem for Cerys will start today, but will take some time.
"Speculation about what happened at the scene and the cause of death is unhelpful and very upsetting for the family of the deceased."
Miss Yemm, who worked in sales at Next, is believed to have met Williams through mutual friends.
A friend, described as a "key prosecution witness", told the Sunday Times that Williams had taken a cocktail of drugs on Thursday evening, when he met Miss Yemm.
"He had an ounce of miaow miaow on him and at some stage during the night he injected himself," the man, who did not wish to be named, told the paper.
"He was also taking large quantities of prescription beta blockers given to him to help overcome his drugs habit."
The man said Williams was given the prescription upon his release from prison a couple of weeks ago.
Friends and local residents have expressed shock at the news of Miss Yemm's death at the Sirhowy Arms Hotel, which used to be a popular local pub.
It was converted into a B&B catering for up to 26 guests and had been used by Caerphilly Council over recent years to provide accommodation for homeless people.
Gareth Griffiths, who lives in Argoed, said: "We heard on the news that it has been cannibalism. Nobody wants to hear that, it must be a horrific way to die, it's horrible, it's unbearable."
Another friend, who did not wish to be named, added: "I feel stunned, shocked and sick to my stomach. It's horrific. She was a lovely person. She didn't deserve to die like that."
Her family are being supported at their home in nearby Oakdale by specialist officers, who said relatives are too distraught to talk to the press.