By the time Bishop Jonathan Ruhumuliza decided to tell the world what was going on in Rwanda, the mass graves of the 1994 genocide were already overflowing.

The Hutu extremist regime that seized power two months earlier had unleashed the notorious militia, the interahamwe, and the army in a systematic attempt to exterminate the country's Tutsi population. The rate of killing was astonishing – 800,000 Tutsis slaughtered in 100 days – as the prime minister and members of his government toured the country egging the murderers on. Even priests were among the killers as churches were turned into killing centres.

But this is not what Ruhumuliza, then a bishop in Rwanda's Anglican church and now a Church of England priest in a Worcestershire village, told the world at the height of the genocide. In letters to foreign churches and a press conference before a tour to Europe and North America, he called the murderous government "peace loving", claimed it was working hard to stop the killings that it was actually organising, and falsely blamed a rebel army for the massacres.

Human rights groups denounced him at that time as a propagandist for the genocidal regime. Even his own archbishop called him an "errand boy" for the Hutu extremist government. Other accusations followed, including from the London-based group, African Rights, that Ruhumuliza allegedly refused shelter to Tutsis facing imminent death.

Two decades later, Ruhumuliza is a priest at the Norman church in the village of Hampton Lovett and under investigation by the Church of England, which said it was not fully aware of the "disturbing" accusations against him until they were brought to its attention by the Observer. The Rwandan authorities are also investigating the bishop as an alleged accomplice to genocide.

Ruhumuliza declined to talk to the Observer about his part in the tragedy.

The former bishop of Worcester, Peter Selby, who appointed Ruhumuliza in 2005, said the Church of England should consider referring the investigation to outside authorities.

"I think that over the whole child abuse thing, it's become clear that what the church has to do, and do immediately, is refer cases to the police. Because there's a recognition that the church, when it has presumed it was competent to deal with such things, clearly wasn't."

The Anglican church is the second largest in Rwanda after Roman Catholicism. The archbishops of both churches were close to the ruling Hutu elite when the genocide broke out. Afterwards they were widelycriticised for their failure to use their influence to try to stop the killings and for their refusal to condemn the politicians organising the massacres. Many of their bishops faced the same criticism, including Ruhumuliza, who was at the forefront of the Rwandan Anglican church's misrepresentation of the genocide.

In May 1994, about five weeks into the killing, Ruhumuliza wrote to the secretary general of the All Africa Council of Churches, Jose Chipenda, defending the genocidal government by parroting the regime's propaganda that blamed the killings on its opponents, the Rwandan Patriotic Front rebels led by Paul Kagame, who is now Rwanda's president. Ruhumuliza wrote that the RPF was "destroying everything, killing everybody they meet while the government is trying to bring peace in the country".

The bishop portrayed the genocide as a populist outburst of anti-Tutsi hatred caused by the rebels' actions and the government as working hard to stop the massacres. He said the prime minister, Jean Kambanda, and members of his cabinet were touring Rwanda to appeal for unity and peace.

"After the setting up of the new government, we see that things are changing in a good way. The ministers are doing their best to bring back peace to the country although they are facing many problems," he wrote to Chipenda.

In fact, Kambanda and his ministers were travelling across Rwanda to urge the killers on and broadcasting speeches that were thinly disguised calls for murder. Kambanda and several members of his cabinet were convicted of genocide by an international tribunal.

In June 1994, Ruhumuliza and the Anglican archbishop of Rwanda, Augustin Nshamihigo, held a press conference in Kenya. The pair again claimed that it was the RPF leading the massacres and that the government was attempting to stop the killing.

"The RPF had planned in advance to kill their opponents. They had weapons to kill these people. This has become a big hindrance to the work of pacification by the interim government, the church and other peace lovers," said Ruhumuliza.

Human Rights Watch offered a scathing assessment. "Far from condemning the attempt to exterminate the Tutsi, Archbishop Augustin Nshamihigo and Bishop Jonathan Ruhumuliza of the Anglican church acted as spokesmen for the genocidal government at a press conference in Nairobi. Like many who tried to explain away the slaughter, they placed the blame for the genocide on the RPF because it had attacked Rwanda. Foreign journalists were so disgusted at this presentation that they left the conference," it said in its comprehensive account of the genocide, Leave None To Tell The Story.

Nshamihigo's successor as archbishop, Emmanuel Kolini, accused Ruhumuliza of collaborating with the Hutu extremistgovernment and described the Anglican church in Rwanda during the genocide as "corrupt".

In 1998, fresh allegations against Ruhumuliza emerged in a document sent by African Rights to the World Council of Churches. It accused him of collaborating with another Anglican bishop, Samuel Musabyimana, who was later charged by the international tribunal with genocide crimes. African Rights said Ruhumuliza refused shelter to Tutsis who were facing imminent death and that he failed to try to save people after another Anglican bishop, Adonia Sebununguri, said a group of Tutsis were "wicked people" who deserved to be killed.

After the genocide, Ruhumuliza was made bishop of Kigali but his presence proved divisive within Rwanda's Anglican church as other clergy demanded he be called to account for his actions. In 1996, he apologised for not speaking out strongly enough against the killings and asked to be pardoned "because I did not continue to energetically condemn either the tragedy which was in progress or the state communiqués which were broadcast on the radios during this time".

The bishop added he should have used the pressconference in Nairobi "to publicly condemn the genocide which was taking place in Rwanda". But Ruhumuliza's critics dismissed the apology because they said his real crime was not what he didn't say but what he did in defending the regime overseeing the genocide.

Despite calls from within the Anglican church for Ruhumuliza to appear before a church court, he was moved to Canada in 1997 and then appointed bishop of Cameroon.

Selby said he had given Ruhumuliza a position in Worcestershire after a letter from the archbishop of Canterbury's office asked if any bishop could find a place for him because he had finished studying in Birmingham and was unable to return to Rwanda. "I saw Jonathan, who comes over as a very nice, humble, pious person," said Selby. "I said: 'Is it the genocide that means you can't go back?', and he said: 'Well the government would let me back. It's just that there are people who, in the aftermath of what happened, might go after me or my family'."

Selby said that as British law requires the consent of the archbishop of Canterbury for foreign priests to take up positions in England, the background check was done by Lambeth Palace. But he said he did later have concerns.

The bishop of Stafford offered the Rwandan priest a job so he could make a living. That required a work permit. Selby said the Home Office spent about two years considering the request and then turned it down in a letter he described as semi-literate. "The only thing it referred to, and the only thing I ever knew about that had ever come up in conversation with Jonathan, was that press conference in Kenya which he has always been disarmingly frank about as a lack of courage on his part, and a lack of good sense and an ill-judged thing to have done. That was the only evidence I ever had of anything that might be called culpable," he said.

But Selby said that Ruhumuliza's "account doesn't square" with what he has now seen in contemporarynewspaper and human rights groups reports of the Rwandan bishop's statements and actions in 1994.

The church paid for Ruhumuliza to challenge the Home Office ruling and the decision was withdrawn before an appeal was heard. He was granted six-month renewable visas.

Selby conceded that there were other concerns, including when Ruhumuliza told him he had made an application for asylum in the UK, that all might not be well during the visa request – the immigration authorities questioned Ruhumuliza for 10 hours.

"I said to him: 'That's a very weird thing for you to do because you've always said that you didn't have a problem with the government of Rwanda. Secondly, that if the government of Rwanda ever raised any issues about which they wished to charge you, you would immediately be prepared to return to Rwanda.' He said that many times in conversations," said Selby.

Selby said that Ruhumuliza replied that he was not afraid of the Rwandan government but of continuing anger in Rwanda over the genocide.

The Church of England would not discuss the accusations against Ruhumuliza but it issued a statement saying that "extensive checks were undertaken through Lambeth Palace" before he was appointed in 2005 and that "no evidence was found of complicity in the Rwandan genocide". It said that Archbishop Kolini had "commended" Ruhumuliza to the archbishop of Canterbury.

But the church added: "We are disturbed by allegations from African Rights, of which we have only just been made aware, and they are being investigated." Kolini, who has retired as archbishop, was not available for comment.Selby said he spoke to his successor as bishop of Worcester, John Inge, and that he was determined to get to the truth.

"He and I are very clear that he has got an issue to deal with and he needs to be the person that deals with that. I don't think we can do other than confront Jonathan with this material. Then we get into our own disciplinary procedures which are quite cumbersome," he said. "This can't be left. No one thinks that it can. It's because he and I were affronted by what we read."

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