Fighting in Cauca province, in the municipality of Argelia, killed 12 combatants from a dissident group of the now-demobilised Revolutionary Armed Forces of Colombia (FARC) rebels, Colombia’s army said.
Dissident FARC groups reject a peace deal signed with the state in 2016.
One soldier was also killed during the fighting, which took place in a mountainous region that is important for drug trafficking.
Elsewhere, seven members of the Clan del Golfo – also known as the Gaitanista Self-Defense Forces of Colombia (AGC) – were killed when troops assaulted one of their camps in Choco province.
Colombia’s army seized long-range weapons, ammunition and communications equipment during the assault, a military spokesman said.
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