Where is John Sweeney now? Serial killer in Until I Kill You

It took years for Sweeney to be brought to justice for his crimes, and Until I Kill You honours Balmer's resilience while also highlighting the failures of the criminal justice system.

Wondering what happened to Sweeney and where he is now? Read on for everything you need to know about the serial killer.

What happened to John Sweeney?

Sweeney was eventually arrested in 2001 for his vicious axe-wielding attack on Balmer back in 1994.

In those six years, Sweeney adopted different aliases and evaded capture by the police but was eventually arrested after links to Paula Fields, a 31-year-old whose headless body was found in London's Regent's Canal in 2001.

However, with no evidence to link him to Fields at the time, he was wanted for Balmer's attempted murder. After she gave her witness testimony in court, Sweeney was found guilty, and made to serve four life sentences.

While imprisoned for Balmer's attack at Gartree Prison in Leicestershire, Sweeney was also questioned about Fields and previous ex-girlfriend Melissa Halstead, whose body was found in a canal in Rotterdam in 1990.

Eventually, the murders of Fields and Halstead were linked in February 2010 and Sweeney was arrested for them. Upon his arrest, several pieces of disturbing artwork were recovered from Sweeney's prison cell in Gartree but the police had also found 300 other pieces of artwork at his North London home, as well as poetry and weapons.

He was handed a life sentence for their murders in 2011 with Judge Mr Justice Saunders saying at the time: "These were terrible, wicked crimes. The heads of the victims having been removed, it is impossible to be certain how they were killed. The mutilation of the bodies is a serious aggravating feature of the murders."

He went on: "Not only does it reveal the cold-blooded nature of the killer, but it has added greatly to the distress of the families to know that parts of the bodies of their loved ones have never been recovered.

"Why the killings occurred, I cannot be sure, but I am satisfied that this defendant is controlling in his relationships with women and, chillingly, that control extends to deciding whether they should live or die."

Sweeney, who chose not to leave his prison cell in Belmarsh for the sentencing, received a further 10-year sentence for perverting the course of justice.

In the trial, Sweeney had continuously denied the murders but the jury heard of how, when he would be rejected by women, he would turn violent. This was evidenced by the graphic artwork that Sweeney produced.

According to Balmer, Sweeney had confessed the murder of Halstead to her and said he killed her because he came back home to their apartment in Amsterdam to find her with two other men. He reportedly told Balmer that he had shot them all and disposed of their bodies in the canal but no other bodies were located.

At the time of Sweeney's sentencing, the Metropolitan Police were trying to find three other women who had possible links to Sweeney and were thought to be ex-girlfriends of his.

Detective Chief Inspector Howard Groves, who led the investigation, said at the time: "As he contemplates a life behind bars, I can assure him that this investigation will continue as we seek to identify and trace other potential victims in the UK, Netherlands and elsewhere in Europe, who may have suffered a similar fate to that of Melissa and Paula."

Where is John Sweeney now?

John Sweeney is currently serving multiple life sentences for the attempted murder of Delia Balmer and murders of Melissa Halstead and Paula Fields.

Until I Kill You is available to watch on ITVX.

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