One of Britain’s most infamous murderers has died in prison, taking to the grave the secret of what happened to his victims’ heads.
John Sweeney, 69, widely known as the “canal killer,” was handed a whole-life sentence in 2011 for murdering two former girlfriends, Paula Fields and Melissa Halstead.
After killing the women, he dismembered their bodies and dumped their remains in canals in London and the Netherlands.
The grim discoveries were made ten years apart, and Sweeney was not connected to the disappearances until after he was convicted of attacking another girlfriend with an axe.
Sweeney died of cancer at HMP Whitemoor in Cambridgeshire on August 14, The Times reported.
A Prison Service spokesman said: “These were horrific crimes and our thoughts remain with the victims and their loved ones.
“As with all deaths in custody, the Prisons and Probation Ombudsman is investigating, and it would be inappropriate to comment further before the conclusion of its findings.”

John Sweeney was jailed for life in 2011 after carrying out gruesome murders and attacks on three of his former partners

Melissa Halstead was an American-born model, originally from Ohio, whose torso was discovered in a Dutch canal on May 3, 1990

Sweeney went on to kill 31-year-old mother Paula Fields, whose body was found in Regent’s Canal, London
Sweeney, a carpenter, boasted of his violence in lurid paintings and poems found at his home – and in one picture, showing a bloody axe, he called himself the Scalp Hunter.
He killed former model Ms Halstead, 33, from Ohio in the United States, in 1990.
Her dismembered body was thrown into a canal in Rotterdam in the Netherlands.
She was only identified 18 years later by DNA, although her head and hands have never been found.
Meanwhile, the body parts of Ms Fields, 31, were found in six holdalls floating in Regent’s Canal in Camden, north London, in February 2001.
Her head, hands and feet are still missing.
Prosecutors during the killer’s trial at the Old Bailey in 2011 said this was a deliberate attempt to prevent the body from being identified.
In addition to the two murders, he also launched an axe attack on a girlfriend, nurse Delia Balmer, who was only saved when a neighbour arrived to help.

Melissa’s body was thrown into the Westersingel canal in Rotterdam in the Netherlands

A drawing by John Sweeney which the prosecution said is a portrait of him and Melissa Halstead

In 1994, Delia Balmer was attacked by Sweeney, pictured together, with a hammer and an axe
Prior to the attempt on her life, Sweeney had held her captive and repeatedly raped her in a week-long ordeal, for which he was arrested but released on bail.
Ms Balmer reported how he had tied her to the bed and threatened her with a gun and a knife, warning her that if she screamed, he would cut her tongue out.
At that time, she had no idea that he had already murdered one former partner, Ms Halstead, and also would go on to kill Ms Fields.
Ms Balmer wrote a memoir about her near-fatal experience living with Sweeney which was adapted into a television mini-series called Until I Kill You by ITV in 2024.
Police also suspect Sweeney may have murdered other former partners.
Two South American ex-girlfriends from the late 90s have mysteriously disappeared, although there is no evidence that any harm has come to them and no one has reported them missing.
Police have been trying to trace Brazilian Irani and Colombian Maria through their consulates, but only have the women’s first names.