Two killers who subjected a woman to four hours of “unimaginable” torture and rape before burning her alive in a car have been told they will never be freed from prison.

Stephen Unwin and William McFall had already been jailed for unrelated murders and freed when they set their sights on Quyen Ngoc Nguyen, a Vietnamese mother-of-two.

Unwin, 40, ran a property maintenance company and met his victim because she helped find homes for other members of the Vietnamese community.

He lured her to his house in Sunderland under the pretext of making a visit to a home on 14 August.

Ms Nguyen, 28, left her job as a nail technician as normal and was last seen alive arriving in Oswald Terrace, Houghton-le-Spring, at 7.30pm that evening.

Newcastle Crown Court heard that 51-year-old McFall was already laying in wait for the horrific attack, when Ms Nguyen was dragged through the house and tortured to extract information including her PIN number.

Both men participated in the attack, which saw Unwin rape her himself and with other objects, and ended with their victim being partially suffocated.

Ms Nguyen was injected with a syringe filled with whiskey before Unwin took her bank cards to a nearby Co-op to withdraw £500.

Quyen Ngoc Nguyen, 28, had two young children (Northumbria Police)

He returned to the house and as she lay incapacitated on the floor, the pair tidied up and casually cooked and ate a curry.

They disposed of Ms Nguyen by wrapping her in a dust sheet and putting her unconscious in the back seat of her Audi, driving it to allotments and setting it on fire.

Forensic evidence presented to the court found it was likely that she was still alive when the car was set alight.

Afterwards, McFall and Unwin took a smiling selfie together while during a trip to withdraw cash from the young mother’s bank account.

Mr Justice Morris said the full horror of what she was subjected to was only known to the two murders, sentencing them both to full life terms without opportunity for parole.

“Quyen Nguyen was a young, healthy and lively woman, a mother of two young children and much loved by her family both here and in Vietnam,” the judge told a sentencing hearing on Wednesday.

“It is not possible for any of us to imagine the horrific ordeal to which she was subjected to over a number of hours on that night, but terrifying it most certainly was.”

Both defendants denied all allegations and McFall heckled the judge from the dock as the sentence was read.

Mr Justice Morris called him an “extremely violent man capable of monstrous behaviour”, while describing Unwin as a “calculating, manipulating and ruthless killer” who had both sexual and financial motivations.

The judge did not find that the murder was racially aggravated but the killers had swapped text messages including a reference to “raping the chink”.

Stephen Unwin was convicted of rape and murder and John McFall was convicted of murder (Northumbria Police)

The pair were already running a criminal enterprise involving stealing highly valuable cannabis crops, including the use of violence and attempts to procure guns.

Unwin has previous convictions for burglary and arson, while McFall has been convicted of numerous offences including for robbery, arson, and possessing firearms and offensive weapons.

The two men were already serving life sentences for brutally murdering pensioners in their homes during the course of unrelated burglaries when they met in prison as cellmates.

Unwin had set the home of his first victim – a 72-year-old man he bludgeoned and stabbed to death on Christmas Day 1998 – on fire in a bid to destroy evidence.

McFall, of Waterloo Road in Blackpool, had murdered an 86-year-old widow with a hammer in 1996 after she disturbed him ransacking her house.

But they were both judged suitable for release on licence in 2010 and 2012 respectively and made contact again around three years ago.

Police tracked and arrested both men the day after finding Ms Nguyen’s body in the burnt-out car, and discovered they had used her bank cards to withdraw a total of £1,000.

They denied any involvement in her murder but were not aware CCTV from a neighbouring home had recorded their movements.

Ms Nguyen, who was just 5ft and weighed seven stone, leaves behind a five-year-old son and six-year-old daughter. She had moved to the UK seven years ago and had studied at a London university.

Her sister, Quynh Ngoc Nguyen, said the family “cannot comprehend” how McFall and Unwin had been allowed to go free after their first murders.

Quyen Ngoc Nguyen, 28, had two young children (Northumbria Police)

“My sister believed, as I did, that you came to this country for a safer life, with better opportunities for herself and her children,” added the 35-year-old, who had attended court for the trial.

“They did not act like human beings, they are evil.”

Quynh said her sister came to England for a “better life” and to improve her education, teaching herself English and living the life she had dreamed of.

“It breaks my heart that I will never see Quyen again but the result today does give us some justice,” she said after the sentencing.

“She was a devoted mother and an amazing sister. I will remember her beautiful smile forever.”

Detective Inspector Ed Small, of Northumbria Police, said the case was one of the worst he had to investigate in 25 years of being a police officer.

“Nobody should ever go through what Quyen endured that night and some of the evidence heard during the trial will haunt her family forever.

“They have shown no remorse throughout and have refused to take any responsibility for their actions.

“The fact they thought they could get away with Quyen’s murder despite the overwhelming evidence against them, shows their level of their arrogance. It is my honest opinion, they will never change.”

UK news in pictures Show all 50 1 /50 UK news in pictures UK news in pictures 18 September 2020 A model presents a creation during the Bora Aksu catwalk show at London Fashion Week 2020 Reuters UK news in pictures 17 September 2020 World kickboxing champion Carl Thomas during his attempt to run a marathon while pulling a plane at Elvington Airfield near York. The attempt is raising funds for Ollie's Army Battling Against Battens, an organisation campaigning to raise GBP 250,000 to fund a clinical trial aimed at saving the sight of children with CNL2 Batten Disease PA UK news in pictures 16 September 2020 Labour deputy leader Angela Rayner speaking during Prime Minister's Questions UK Parliament/AFP/Getty UK news in pictures 15 September 2020 People enjoying the autumn sunshine as they punt along the River Cam in Cambridge PA UK news in pictures 14 September 2020 Early morning light bathes the skyscrapers of the City of London, at the start of a week in which the UK is expected to bask in temperatures of more than 30 degrees PA UK news in pictures 13 September 2020 England celebrate after they dismissed Australia's Alex Carey to win the second ODI match of the series at Emirates Old Trafford, Manchester PA UK news in pictures 12 September 2020 Protesters outside BBC Broadcasting House in central London, as marches and rallies form across the country calling for a 15% pay rise for NHS workers and an increase in NHS funding PA UK news in pictures 11 September 2020 An empty migrant dinghy floats off the beach at St Margaret's Bay after the occupants landed from France in Dover Getty UK news in pictures 10 September 2020 A view of small boats thought to be used in migrant crossings across the Channel at a storage facility in Dover, Kent PA UK news in pictures 9 September 2020 EU's chief negotiator Michel Barnier, left, arriving from the Eurostar with EU Ambassador to the UK, Portuguese diplomat Joao Vale de Almeida at St Pancras International railway station, London, for the latest round of the negotiations on a free trade deal between the EU and the UK PA UK news in pictures 8 September 2020 Dawn over Coquet Island, a small island off Amble on the Northumberland coast PA UK news in pictures 7 September 2020 A hovercraft arrives to Southsea, Hampshire from the Isle of Wight PA UK news in pictures 6 September 2020 Forensics officers near the scene of multiple reported stabbings in Birmingham Reuters UK news in pictures 5 September 2020 Anti-migrant protesters demonstrate in Dover against immigration and the journeys made by refugees crossing the Channel to Kent PA UK news in pictures 4 September 2020 Activists take part in a demonstration against the HS2 hi-speed rail line outside the Department of Transport AFP via Getty UK news in pictures 3 September 2020 Peter Baker, who plays Trigger in the musical version of Only Fools and Horses, sweeps the stage of the Theatre Royal Haymarket in London, after observing a 15 minute silence to show solidarity with those in the theatre industry that have lost their jobs due to the coronavirus pandemic PA UK news in pictures 2 September 2020 Kadie Lane, right, 11, and Brooke Howourth, 11, hug on their walk to Marden Bridge Middle School in Whitley Bay, Tyne and Wear, for their first day of term, as schools in England reopen to pupils following the coronavirus lockdown PA UK news in pictures 1 September 2020 Extinction Rebellion protesters sitting outside The Houses of Parliament in Westminster, London PA UK news in pictures 31 August Surfers at Long Sands Beach, Tynemouth PA UK news in pictures 30 August Black Lives Matter protesters march through Notting Hill in London in the first Million People March EPA UK news in pictures 29 August A protester reacts as she demonstrates against the lockdown and use of face masks, amid the coronavirus disease outbreak, outside Downing Street in London Reuters UK news in pictures 28 August Caribbean soca dancers display their costumes as they promote the first ever digital Notting Hill Carnival, following the cancellation of the normal Carnival festivities due to the continued spread of the coronavirus disease, in London Reuters UK news in pictures 27 August Father and son team Chris and Sam Milford from historic building conservation specialists WallWalkers begin restoration work on the spire of Norwich Cathedral, which stands at over 312ft high. The first known spire was completed in 1297 PA UK news in pictures 26 August Giant waves at Seaham in County Durham, as the bad weather continues PA UK news in pictures 25 August An assistant at the Wallace Monument cleans the case which houses the William Wallace sword in the Hall of Arms room at the monument near Stirling as they prepare to re-open PA UK news in pictures 24 August Restored World War Two landing craft LCT 7074 is transported from from the Naval Base in Portsmouth to its final resting place at the D-Day Story at Southsea PA UK news in pictures 23 August Jenny Nguyen and Tony Cao, from Vietnam, pose for wedding photos on Tower Bridge in London, as it remains closed to vehicles after it was stuck open on Saturday due to a "mechanical fault". The landmark's Twitter account confirmed only pedestrians and cyclists could use it on Sunday morning PA UK news in pictures 22 August England's Zak Crawley hit 267, joining the exclusive Double Hundred club, on day two of the Third Test match against Pakistan at the Ageas Bowl, Southampton PA UK news in pictures 21 August Harri Teale gathers lavender during the annual harvest on the Wolds Way Lavender farm near Malton in North Yorkshire PA UK news in pictures 20 August Parents and a student react after checking GCSE results at Ark Academy in London Reuters UK news in pictures 19 August Tate Modern workers hold a strike outside the gallery in London, to protest the institution's announcement that it would cut more than 300 jobs from its commercial arm, Tate Enterprises PA UK news in pictures 18 August Two rescued brown bear cubs, Mish (left) and Lucy, cool off in a pool after arriving at their new home with the wildlife conservation charity Wildwood Trust in Herne Bay, Kent. The orphaned pair, who have been living in a temporary home in Belgium since they were found abandoned and alone in a snowdrift in the Albanian mountains, will be acclimatised to their new life in the country before moving to a permanent home PA UK news in pictures 17 August A level students celebrate outside the Department for Education in London after it was confirmed that candidates in England will be given grades estimated by their teachers, rather than by an algorithm. The government U-turn comes just days after Education Secretary Gavin Williamson vowed there would be "no U-turn, no change. PA UK news in pictures 16 August Wasp players take a knee as Northampton Saints stand prior to kick-off in their Premiership match at Franklin's Gardens PA UK news in pictures 15 August Piper Colour Sergeant Lil Bahadur Gurung attends the VJ Day National Remembrance event, held at the National Memorial Arboretum in Staffordshire, Britain Reuters UK news in pictures 14 August People including students hold placards on Whitehall outside Downing Street as they protest against the downgrading of A-level results. The government faced criticism after education officials downgraded more than a third of pupils' final grades in a system devised after the coronavirus pandemic led to cancelled exams yes AFP via Getty UK news in pictures 13 August Benita Stipp (centre) and Mimi Ferguson (left) react as students at Norwich School receive their A-Level results PA UK news in pictures 12 August 2020 A train derailment near Stonehaven has left three people dead. Driver Brett McCullough, conductor Donald Dinnie, and a passenger were killed when the 6.38am Aberdeen to Glasgow Queen Street service crashed amid heavy rain and flooding BBC UK news in pictures 11 August 2020 A woman hydrates in the sun after open water swimming at the West Reservoir Centre in north London Tolga Akmen/AFP via Getty UK news in pictures 10 August 2020 Prime Minister Boris Johnson takes part in an archery session as he visits Premier Education Summer Camp at Sacred Heart of Mary Girls' in Upminster Reuters UK news in pictures 9 August 2020 People cycle through Cambridge as the heatwave continues in Britain EPA UK news in pictures 8 August 2020 Healthcare workers take part in a protest in London over pay conditions in the NHS Getty UK news in pictures 7 August 2020 Emergency services make their way along the seafront on Bournemouth beach in Dorset on one of the hottest days of the year PA UK news in pictures 6 August 2020 Alison Murphy poses for a picture by husband Peter as she walks through a field of sunflowers in Altrincham, Cheshire PA UK news in pictures 5 August 2020 Pakistan's Abid Ali being bowled by England's Jofra Archer during day one of the First Test match at the Emirates Old Trafford, Manchester PA UK news in pictures 4 August 2020 The 'Timbuktu tumblers' from Kenya perform their balancing act on the Southsea waterfront as Zippos Circus reopens in Portsmouth Rex UK news in pictures 3 August 2020 Pelicans interact with a visitor in St James's Park in London PA UK news in pictures 2 August 2020 Lewis Hamilton drives with a puncture towards the finish line to win the Formula One British Grand Prix at Silverstone POOL/AFP via Getty UK news in pictures 1 August 2020 Arsenal's Pierre-Emerick Aubameyang celebrates with the trophy and teammates after winning the FA Cup, as play resumes behind closed doors following the outbreak of the coronavirus disease Pool via Reuters UK news in pictures 31 July 2020 People enjoy the sunny weather at a Bournemouth Beach Reuters

He added: “The sentence handed to William McFall and Stephen Unwin today means they will never be released to kill again.