Warning: This article contains details that some readers may find distressing.
A Kenyan activist has told the BBC that he is "struggling to be alive" after allegedly being sexually tortured in detention in Tanzania last month.
Boniface Mwangi said he had decided to speak despite the "shame and guilt of being sodomised with all manner of things".
Mwangi said he was held in Tanzania after going to the country to show solidarity with detained opposition politician Tundu Lissu.
At a press conference in Kenya's capital, Mwangi tearfully claimed that he was stripped naked, hung upside down, beaten on his feet and sexually assaulted while detained.
The police chief in Tanzania's main city of Dar es Salaam disputed Mwangi's account and told the BBC they were "opinions" and "hearsay" coming from activists.
"If they were here, I would engage them, I would ask them what are they saying, what do they mean... In law, those things are called hearsay or hearsay evidence," Jumanne Muliro told the BBC.
Tanzanian President Samia Suluhu Hassan's government has been accused by rights groups of becoming increasingly repressive in the run-up to October's presidential and parliamentary elections.
She attended the press conference in Nairobi on Monday, where Mwangi described his sexual assault in graphic detail.
Mwangi added that the officers told him they were filming everything and would leak the footage if he spoke about what he had gone through.
Mwangi told the BBC Newsday programme that the torture had left him in mental anguish.
Mwangi said he wanted his medical records be made public so that "what happened to me should never happen to anyone else".
Mwangi and Atuhaire were among several activists who travelled to Tanzania two weeks ago in solidarity with Lissu who was appearing in court on treason charges that he denies.
Lissu was arrested on 9 April following his rallying call of "no reforms, no election".
President Hassan warned at the time that she would not allow activists from neighbouring countries to "meddle" in Tanzania's affairs.
The whereabouts of Mwangi and Atuhaire were unknown while they were being held, sparking widespread condemnation.
"So having been abducted during broad daylight and never knowing where I was, and I was still tortured, means that the Tanzanian government doesn't care about what people think about it," he told the BBC.
Mwangi said their experience showed "how broken" countries in East Africa were.
The US Department of State's Bureau of Africa Affairs previously said it was deeply concerned by the reports of the two activists' mistreatment, noting that Atuhaire had been recognised by the department "in 2024 as an International Women of Courage Awardee".
Additional reporting by Munira Hussein in Dar es Salaam.
