John Williams Ntwali, one of Rwanda's few journalists who published stories critical of the government, has died.

Ntwali was the sole fatality in a car accident in Kigali on Wednesday, police spokesman John Bosco Kabera told Reuters. The driver of the other vehicle has been arrested and "the accident file is being processed for onward transmission to prosecution," Kabera said.

Numerous human rights organizations called for an independent investigation into his death, as numerous journalists, advocates, and critics of President Paul Kagame and his ruling party have mysteriously disappeared, been found dead, or been jailed.

Human Rights Watch said he "joins a long list of people who have challenged the government and died in suspicious circumstances."

"John Williams Ntwali was a lifeline for many victims of human rights violations and often the only journalist who dared report on issues of political persecution and repression," said Lewis Mudge, Central Africa director at Human Rights Watch.

In Rwanda, the media environment is oppressive, tightly controlled, and dangerous. During the last two decades, 17 journalists have been killed, according to data collected by the Committee to Protect Journalists. As the editor of the newspaper The Chronicles, Ntwali investigated high-profile political trials, corruption cases, and other sensitive issues. He often posted items on his social media feed and YouTube channel critical of the government's approach. On Jan. 10, Ntwali posted on his Twitter account a report that the Rwandan government was meddling in religious administration.

He had been arrested numerous times throughout his career and spoke often about fearing for his life and safety.