Nicholas Rossi, who fled from the US to Scotland after he faked his own death to avoid rape charges, has died in hospital.
Rossi, originally from Rhode Island, was jailed last year for raping two women in Utah in 2008.
The Utah Department of Corrections said the 38-year-old was pronounced dead at a local hospital.
It said: "Rossi died from complications of an existing medical condition after choosing to discontinue medical treatment.
"This notification follows communication with Rossi's family and his victims."
It added: "Rossi was serving a cumulative sentence of 10 years to life for two counts of first degree felony rape."
Utah authorities said they could not disclose details about Rossi's health problems, but in court hearings he often appeared in a wheelchair and used oxygen.
He was convicted separately in August and September last year of raping two women.
Rossi left a "trail of fear, pain and destruction" behind him, one of the victims told a court before Rossi was sentenced in October.
"This is not a plea for vengeance. This is a plea for safety and accountability, for recognition of the damage that will never fully heal," she said.
In his first Utah trial, Rossi's public defender denied the rape claim.
The victim told a court in Salt Lake County that she and Rossi began a relationship while she was recovering from a traumatic brain injury in 2008.
The woman said they began dating after she responded to a personal ad Rossi had placed on Craigslist, and they quickly became engaged.
She said she paid for their dates and covered Rossi's rent.
The relationship soured when Rossi started "becoming controlling and saying mean things to me", she told the court.
On the day she was raped, she said Rossi had pounded on her car and used his body to block her from pulling out of a garage.
After she agreed to enter the house to talk, he pushed her on to his bed, held her down and "forced me to have sex with him", she testified.
How Rossi was caught
He was first identified in 2018 after a decade-old DNA rape kit was examined.
But in February 2020 - months after he was charged in one of the cases - an online obituary claimed he had died of non-Hodgkin lymphoma.
Rossi was arrested in Scotland the following year while being treated for COVID, after hospital staff recognised his distinctive tattoos - including the crest of a university he never attended - from an Interpol red notice.
A protracted court battle meant he wasn't extradited until January 2024, with Rossi claiming he was an Irish orphan named Arthur Knight who was being framed.
Rossi claimed that he had been given the tattoos while he was in a coma in hospital so that he resembled the wanted man.
At one stage he claimed he was so unwell he was unable to raise his arms above his head, despite having visibly done so in court a day earlier.
In a bizarre appearance at a Utah court after his extradition, Rossi spoke in an apparent English accent and referred to the judge as "m'lady" and gave his name as Arthur Knight Brown in a laboured, breathy tone.
Investigators identified at least a dozen aliases that Rossi, whose legal name was Nicholas Alahverdian, had used to evade capture over the years.
Rossi had married a woman in Bristol and the pair moved to Glasgow.
(c) Sky News 2026: Nicholas Rossi, the US rapist who faked his death and fled to Scotland in bid to escape justice,

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