An independent health watchdog says it's carrying out a review into how a man with paranoid schizophrenia was released from hospital, and went on to murder a woman from Norwich.
Deyan Deyanov beheaded Jennifer Mills-Westley in Tenerife in 2011, less than a year after treatment in Glan Clwyd hospital in Wales.
The Healthcare Inspectorate says the report into decisions were made by the Betsi Cadwaladr health board is due to be completed by next summer.
The daughters of a former Norfolk woman beheaded in Tenerife have met the killer's family in North Wales to discover more about him in their quest for an independent review into how he remained free to murder.
In February homeless Bulgarian drug addict Deyan Deyanov, 29, was sentenced to 20 years in a secure psychiatric unit on the holiday island after slaying former road safety officer Jennifer Mills-Westley, 60.
Deyanov - who had been sectioned in North Wales in 2010 under the Mental Health Act - attacked the victim while she was shopping in the popular resort of Los Cristianos in the Canary Islands, on May 13 2011.
Deyanov, a delusional drifter living rough in a derelict building on Tenerife's Los Cristianos beach, used crack cocaine and LSD and built a shrine full of religious imagery.
His history of violence can be traced back to his hometown of Ruse, a city in northern Bulgaria known as the Little Vienna.
After leaving Bulgaria, he drifted all over Europe, staying in Edinburgh, North Wales and Ibiza, before arriving in Tenerife.
Released from North Wales care in October 2010 he travelled to Tenerife.
He believed he was Jesus Christ and heard voices commanding him to kill.
Well-known as a troublemaker he had been arrested on the island at least four times between January and May 2011.
In January 2011 he committed a series of random violent attacks and was committed to La Candelaria hospital's psychiatric unit, but was released on bail in early February.
Days before he killed Mrs Mills-Westley an arrest warrant was issed for him.
After his conviction, the victim's two daughters Samantha Mills-Westley, 39, and Sarah Mills-Westley, 43, hit out at the authorities for their handling of Deyanov.
Tonight, in a Channel 4 Dispatches programme, the sisters, who are calling for an independent review, meet the killer's aunt in North Wales to ask if he received the right care.
The programmes airs at 8pm.
A man from Essex who's been cleared of drowning a fellow passenger on a booze cruise in Tenerife nearly 17 years ago has been telling ITV News Anglia about how it's affected his life.
Darren Sapstead, from South Woodham Ferrers, was accused of pushing Garry Walton from Ireland overboard. The case was originally treated as an accident but in 2005 Mr Sapstead was extradited to Spain.
Mr Sapstead was extradited in 2005 and spent 8 months in jail in Spain before returning home on bail. Last week he was acquitted by a jury.
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A man from Essex has been cleared of killing a tourist in Tenerife by throwing him overboard from a boat.
Darren Sapstead, 38, from Chelmsford, was acquitted by a jury at a Santa Cruz court in Tenerife.
Garry Walton, 21, of County Waterford, Ireland, drowned in 1996 while on an excursion.
The family of a woman from Norfolk savagely attacked in Tenerife, today came face to face with her alleged killer.
60-year-old Jennifer Mills-Westley had retired to the holiday island when she was the victim of a gruesome crime.
Today (Monday) her two daughters watched in horror as close circuit television footage of the attack was shown in court.
The man accused of murdering her told the jury he'd been haunted by voices - and sometimes they told him to kill.