The soldiers came at dawn to Fulgence Rukundo's house in a village in western Rwanda, and accused him of stealing a cow.
They draped slabs of the dead cow's carcass around his shoulders and positioned the animal's head on his before marching him into a banana plantation and shooting him dead, according to witnesses cited in a Human Rights Watch (HRW) report on extrajudicial killings released Thursday.
An investigation by the rights group alleges that Rwandan security forces executed at least 37 suspected petty offenders, including Rukundo, instead of prosecuting them. Another four have allegedly disappeared.
The government refused AFP requests to comment on the report released a day before the start of election campaigning for August 4 elections in which incumbent President Paul Kagame is expected to handily win a third term.
According to HRW, the wave of documented extrajudicial killings took place between July 2016 and March 2017 in western Rwanda and appeared to be part of an official strategy to "spread fear, enforce order and deter any resistance to government orders or policies."
"In most of the cases documented by Human Rights Watch, local military and civilian authorities told residents after the execution, often during public meetings, that they were following 'new orders' or a 'new law' stating that all thieves and other criminals in the region would be arrested and executed," the report says.
Despite occurring in front of multiple witnesses, the killings have not been discussed in Rwanda, where the media has been muzzled and local rights groups are afraid to speak out, according to HRW.
After being taken from his home, Rukundo was first marched to a public meeting, with hundreds of villagers following the grisly spectacle, where the mayor accused him of stealing the cow.
"All thieves must be killed," the mayor said, according to a witness at the meeting, before signing a piece of paper along with the soldiers who then took him away and shot him, the report says.
One resident from the Rubavu district told HRW that warnings were delivered in regular community meetings, an important part of village life in Rwanda.