Manoel Santos was gay and feared persecution for his sexuality in his native country, so, after the Home Office served him his deportation notice, he took his own life, Stella Moris said on Twitter. Santos had lived in the UK for 20 years, she added.

“Manoel was at high risk. His suicide was foreseeable. An inquiry into his case might prevent future suicides,” she wrote.

Assange himself is “devastated” at Santos’s death, Moris said, conveying his condolences to the Brazilian’s friends and family. Santos had been incarcerated in the same prison block as Assange and occasionally helped him with letters received in Portuguese. He was also “an excellent tenor,” she said.

Moris, a lawyer and a mother to two children with Assange, said her partner hopes the British government will conduct an investigation into the decision to extradite his late friend.

The story bears a clear parallel to that of Assange himself. The Wikileaks founder is being detained at the notorious maximum-security prison in London until his extradition trial. If handed over to the US, he will be tried under the Espionage Act and may spend the rest of his life behind bars.

His supporters have repeatedly warned that both Assange’s physical and mental health have seriously deteriorated. They have petitioned the British government to release him on bail, a request that was denied.

Assange is accused by the US of various computer crimes, including helping whistleblower Chelsea Manning in her leaking of classified US military documents to Wikileaks in 2010. His supporters see the case as a major threat to freedom of the press worldwide, arguing that Washington is trying to punish him for publishing materials that proved embarrassing to the US government.