A Congolese general recruited, financed and armed elements of a Ugandan Islamist group to kill civilians while he was in charge of a military operation targeting the rebels, according to a confidential report to the United Nations Security Council.
A panel of U.N. experts, who monitor sanctions on Democratic Republic of Congo, said "it has become clear that FARDC (Congolese army) officers were involved in recruiting and supplying armed groups involved in the killings (of civilians)."
More than 500 people have died in a wave of attacks in eastern Congo since October 2014, rights groups say. The Congolese government has blamed most of those on the Allied Democratic Forces (ADF).
Brigadier General Muhindo Akili Mundos was in charge of the offensive against the ADF - named Sukola, or "cleanup" in the local Lingala language - between August 2014 and June 2015.
"The Group knows of eight individuals that were approached in 2014 by General Mundos to participate in the killings," the experts wrote in the report, seen by Reuters.
Three members of the ADF-Mwalika, a splinter group of the core ADF, told the experts that before the killings began Mundos had persuaded elements of their group to merge with other recruits.
"According to them, General Mundos financed and equipped this group with weapons, ammunition and FARDC uniforms. He came to their camp several times, sometimes wearing an FARDC uniform and sometimes in civilian clothes," the experts said.
"Although it is unclear if they knew what the objective was initially, these three ADF-Mwalika elements were eventually given the order to kill civilians," they said.
Mundos told Reuters on Saturday that the accusations against him were false and the killings had continued after he left the operation.
The U.N. report also contains accusations of links between other Congolese army officers and the ADF. The Congolese army and the Congolese government did not immediately respond to requests for comment on Saturday.
The U.N. experts said that while the number of killings had decreased since Mundos was transferred from the Sukola operation in June 2015, "the killings of civilians have continued by armed elements throughout 2015 and early 2016."
In March, Jason Stearns, a former coordinator of the U.N. panel of experts who now heads the Congo Research Group at New York University, accused Congolese soldiers of taking part in at least three deadly attacks on civilians.