A serial wife killer who met his third victim while on day release from a secure mental hospital is likely to die in jail.
Violent and "controlling" Theodore Johnson, 64, kept his relationship with Angela Best a secret from authorities for 15 years and did not let on about his past to his new partner until after she confronted him with letters about it.
When she left him and started a new relationship, he attacked the 51-year-old mother-of-four and grandmother, beating her over the head with a claw hammer and throttling her with her leopard print dressing gown belt.
He then jumped in front of an express train at Cheshunt station in Hertfordshire.
As he was being treated for severe injuries, police went to his flat and found Ms Best dead in the living room.
Johnson, who is now confined to a wheelchair, pleaded guilty at the Old Bailey to murdering Ms Best on December 15 2016, and was jailed for a minimum term of 26 years.
Judge Richard Marks QC said: "The attack by you on Angela Best was sustained, vicious and utterly brutal. She suffered an unimaginably terrible death."
Johnson's crime was aggravated by the fact it was his third killing of a female partner and that he repeatedly lied and concealed from authorities that he was with Ms Best.
Prosecutor Mark Heywood QC said Johnson had a violent history towards the women in his life, having been convicted of manslaughter twice before.
In 1981, he was found guilty by reason of "provocation" of killing his wife Yvonne Johnson by pushing her off the ninth-floor balcony of their home in Wolverhampton.
Then, in 1993, a couple of years before meeting Ms Best, he was convicted of strangling his common law wife Yvonne Bennett with a belt at their home in London before trying to hang himself.
He was found to be suffering from depression and a personality disorder and was handed a hospital order with restrictions at the Old Bailey.
Mitigating for Johnson, Annette Henry QC said her client was likely to die behind bars.
She said: "He does not wish to be alive. He hates himself for what happened. We recognise the devastation felt by the family members."
She said the mental health tribunal's condition on Johnson's release was flawed as it relied on "self reporting" any new relationship.
She said: "This was a dilemma and the tribunal found it was fraught with difficulty in trying to monitor."
Judge Marks said: "This was a deception that must have gone on for something like 15 years."
Camden and Islington NHS Trust, which was responsible for Johnson's care in the community since 2004, said it would provide Ms Best's family with an independent report and that Johnson's treatment complied with conditions set by the Mental Health Tribunal which oversaw his discharge in 1997.
Sentencing, Judge Marks told Johnson: "Such repeated offending, resulting in three separate court cases, must be almost unprecedented."