Burundi is commemorating the one-year anniversary of the death of three Italian nuns, who were raped and decapitated in a series of murders that shocked the country in September 2014.

Lucia Pulici, who was 75, and Olga Raschietti, 82, were found decapitated in their dormitory on the Sunday, while a third nun, 79-year-old Bernadetta Boggian, was murdered the following night, despite a police guard at the convent.

"It is very difficult to know the reason behind the killing, but nothing can justify it," Father Mario Pulicini, who is responsible for the parish in the northern suburb of Bujumbura of Kamenge, said at the time.

The criminal commando theory

One man, Christian Claude Butoyi, described as mentally ill, was promptly arrested, but in January − four months after the murders − the Radio Publique Africaine (RPA) aired the testimony of a man claiming to belong to a criminal commando unit who he insisted committed the murders.

Three nuns murder suspect
A Burundian policeman escorts suspect Christian Claude Butoyi (C) after he was arrested in Bujumbura for the murder of three Italian nuns Esdras Ndikumana/AFP/Getty Images

The recording suggested the commando was linked to Adolphe Nshimirimana, widely seen as the country's internal security chief and a powerful general loyal to President Pierre Nkurunziza. Nshimirimana was killed in a rocket attack on August 2.

According to claims by Burundi's most popular radio station, known to be supportive of the opposition, Nshimirimana personally greeted the commander responsible for instigating the nun's murders in a restaurant that is said to have served as the general's headquarters.

In the recording, the man, who said he has been in hiding since, in fear of his life, also alleged that members of the commando accepted the mission for €50,000 (£36,557, $55,830).

Bob Rugurika's arrest

A few days later, the RPA's director Bob Rugurika was arrested and charged with complicity in the murder of the nuns – after he refused to reveal the identity of his source. The journalist spent a month in prison in Muramvya before he was granted bail and released on 18 February.

Bob Rugurika release prison
Burundians gather outside the headquarters of the Radio Publique Africaine (RPA) in Bujumbura to welcome the release on bail of its director Esdras Ndikumana/AFP/Getty Images

"You know, people who decided to arrest me, people who decided to detain me, were recruited from the people involved in (the nuns') murder. That I'm not afraid to say it because we showed it in the information we broadcast and we will continue to show it in the future. These people thought that, by arresting me, they could bury this story but this came back to haunt them. Sooner or later, they will pay for it," Rugurika told Iwacu the day of his release.

One year on, and the investigation into the deaths seems to have stalled. While the Public Prosecutor's office told IBTimes UK seven people were arrested and have been interrogated, it said the case "had not yet arrived at the office".

"There has been no progress," the public prosecutor's office admitted.

For Innocent Murenzi, a Burundian journalist, the inquiry has been "buried". "Justice has been denied," he told IBTimes UK. A resident of Rohero asked: "Where is Burundi's impartial justice?"

The motive was unlikely to be a botched burglary, since money and valuable religious artifacts made of silver were not taken from the house, according to local reports. The parish of Guido Maria Conforti in Kamenge held a mass to commemorate the one-year anniversary of the deaths of the nuns, who had been living in Burundi for over six years, on Saturday (5 September).

A foundation stone was blessed in preparation for the construction of a chapel to be dedicated to the victims.

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