Boali, Central African Republic - Kounamon Maurice was finally able to bury his younger brother Kolofio Robert in February, more than a year after he disappeared.
His family says Robert, along with 11 others, was executed by soldiers from Congo Brazzaville who were part of an African Union peacekeeping force.
As he seeks justice, Maurice looks after Robert's six children.
"We've been meeting human rights people. My concern is that justice is done," he said. "He's left me with children, I don't have a job, I can't take care of them and I don't even have the power to follow up on his death."
Robert was an area leader of anti-balaka, a Christian rebel group which has been one of the groups fighting a sectarian war in the Central African Republic.
People in Boali, the north eastern town where Robert is from, say he had kept the peace but an altercation with a Congolese AU commander could have led to his death.
Pregnant woman killed
Most of the graves alongside Robert are marked unknown because identifying the highly decomposed bodies was difficult.
Among the bodies was a pregnant women.
"What I saw was just skull and bones. I couldn't tell who was who but I knew it was them because of the clothes and some jewellery," said Dabele Nguile Frederick, who witnessed the exhumation.
The twelve who were killed were well known, Frederick said, adding that he believed they were murdered at a military base close to the field in which they were buried.
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A United Nations mission took over from African Union forces in September 2013. Since then, the UN has sent AU soldiers accused of murder back to their home countries.
"Until now there has been no accountability, there has been no judicial process to hold these murderers accountable and this has reinforced this notion in the mission and this has transferred over to the UN that you can get away with it," Lewis Mudge, a researcher in the Africa Division at Human Rights Watch (HRW), told Al Jazeera.
HRW investigated the deaths of 18 people killed between 2013 and last year.
While Congolese military officials say they are independently investigating the recent deaths, those at the African Union have handed over the case to the UN.
African Union Commissioner for Peace and Security, Smail Chergui, said: "I think we usually establish special inquiry teams to look into the facts. The UN has certainly taken this up and we'll see the outcome of those inquiries then make a determination."
The process has been long and those whose family members were killed are still waiting for answers. They say simply sending troops away is not enough.
Al Jazeera is seeking comment from the African Union and the United Nations.
Follow Catherine Soi on Twitter: @c_soi
