Rights organisations are urging Rwanda to allow an independent investigation into the death in custody of outspoken government critic Aimable Karasira, whose case has reignited concerns over the treatment of dissenting voices in the country.

Rwandan authorities say Karasira, a former university lecturer and popular YouTube commentator, died from a drug overdose while being held at Nyarugenge prison hospital in Kigali. Officials have described the death as a medical matter, insisting he had been receiving treatment and that there was no foul play.

Human Rights Watch has rejected that account as insufficient and called the circumstances “highly suspicious.” The organisation said the Rwandan government bears the burden of demonstrating that Karasira was not unlawfully killed and that his detention conditions met international standards.

According to the group, Karasira had long been a target of harassment and intimidation because of his outspoken criticism of the authorities and his commentary on the legacy of the 1994 genocide. His online videos, in which he questioned official narratives and raised sensitive political issues, drew a large following but also the attention of security agencies.

Karasira was arrested in 2021 and charged with genocide denial, justifying genocide, and sowing division among the population. Prosecutors accused him of using social media to undermine national unity. He denied the charges, arguing that he was exercising his right to free expression. A Rwandan court later convicted him on some counts and acquitted him on others.

Human Rights Watch says his death fits a troubling pattern of unexplained deaths of detainees and critics in state custody. The organisation pointed to the case of gospel singer and government critic Kizito Mihigo, who was found dead in a police cell in Kigali after being arrested while allegedly attempting to flee the country. Authorities ruled Mihigo’s death a suicide, a conclusion that many Rwandans and international observers have questioned.

Opposition figures and exiled activists now argue that only an inquiry led by independent forensic experts and overseen by international observers can credibly establish what happened to Karasira. They warn that without transparency, his death will deepen fear among government critics and further erode confidence in Rwanda’s justice system.