An armed group has attacked a United Nations convoy in southeastern Colombia, setting fire to two vehicles, the organization said Thursday.

The UN mission that monitors adherence to a 2016 peace deal with the former FARC guerrillas said it "firmly rejects the attack suffered by our team" in Puerto Nuevo, located in a rural area of Guaviare department.

According to the United Nations, its workers were traveling with members of the UN Office for Humanitarian Affairs (OCHA) and the Norwegian Refugee Council when "they were approached by armed men who made them get out of their vehicle."

"Two of the three vehicles were set on fire" by the perpetrators, the statement said. Members of the convoy, however, "returned unharmed" to their offices.

Senior presidential adviser Emilio Archila told local radio that the "criminals presented themselves as dissidents" of the former FARC guerrillas, under the command of Gentil Duarte, one of Colombia's most wanted men.

Created under the 2016 peace agreement between the Revolutionary Armed Forces of Colombia (FARC) and the government of Nobel Peace Prize winner and then president Juan Manuel Santos, the UN Verification Mission in Colombia monitors implementation of the accord, which led to the disarmament of some 7,000 guerrillas.