The sister of a Vietnamese woman who was tortured by two convicted murderers has said they are evil and should die behind bars.

Nail bar owner Quyen Ngoc Nguyen suffered unimaginable horror at the hands of Stephen Unwin and William McFall, who teamed up after meeting in prison when they were serving life sentences.

Her sister, Quynh, 32, said that for the safety of the public they should never be released.

Speaking through an interpreter, she said: "I don't want to blame anyone but it seems that the Government is too kind to these people, because what they have done is terrible.

"My sister has passed away and nothing can change that.

"But I believe that if these two people were released at some point in the future, then definitely some innocent people could be harmed.

"I think they should never be released, they are evil."

Asian Image:

Stephen Unwin (left) and William McFall who have been been convicted at Newcastle Crown Court for the murder of Quyen Ngoc Nguyen. 

The sisters ran a nail bar in Gateshead, and lived together in Killingworth, North Tyneside, bringing up their children in the same house.

When she heard the news that her sister had been murdered, Quynh could not bring herself to tell their parents in Vietnam.

She described her sister as trusting but also naive.

She has followed the court proceedings, despite the torment of hearing in detail the ordeal her sister faced.

Quynh, holding a framed photo of Quyen, said: "I took all the courage that I have in order to know exactly what happened to my sister.

"But sometimes when I hear the stories from the two defendants, I was so resentful, I couldn't control myself.

"They make up stories that you just cannot imagine how they do things like that."

Quyen came from Vinh, a city in the north of Vietnam, and moved to the UK in 2010 to study business in London.

As well as working in the nail bar Quyen helped Vietnamese people who may not have had the correct documents to find accommodation.

Killers met in the prison system

The jury heard how her killers ate a curry they had cooked as their victim lay dying in the house.

The mother-of-two worked at her sister's nail bar but also helped Vietnamese people find accommodation when she came across Unwin, who worked for landlords maintaining properties.

She would not have known he was a life prisoner out on licence for murdering a pensioner in 1998.

Tellingly, he also set fire to his elderly victim's house in a bid to cover his tracks.

McFall, who is from Northern Ireland, also murdered a pensioner during a 1996 break-in.

The killers met in the prison system at HMP Swaleside, a Category B institution, in Kent. They got in touch via Facebook after they were both released on licence.

They teamed up, working together legitimately, but also stealing cannabis from farms they found in local properties.

They planned their depraved attack on the 5ft victim and Unwin tricked her into coming into his home, where McFall was waiting.

The Irishman had texted Unwin earlier that evening saying: "We raping the chink"?

Before she was sexually assaulted, raped and killed, she had been forced to hand over her PINs and Unwin withdrew £1,000 from her bank accounts at cashpoints that night.

Each of the defendants blamed the other, seemingly hoping to confuse the jury.

McFall wrote to Unwin while they were on remand saying he had been to the prison library and found a "legal loophole" despite what he admitted was damning evidence.

The prosecution claimed their loophole was simply to blame one another.

By Tom Wilkinson