The military facility in the town of Aguachica was attacked with drones and explosives that detonated during the night of Friday, the country's army announced. About 30 soldiers were injured in the attack.
The militant leftist ELN, which emerged in the mid-1960s, is one of the last guerrilla movements active in Latin America. It controls large areas of Colombia where drugs are produced.
Unlike other militant leftist groups, including the country's former leading Farc guerrilla, negotiations with the central government in Bogotá have not led to a peace settlement.
The attack on the military and police was the ELN's second in the past week. On Tuesday, two police officers were killed in an attack in the city of Cali.
The group “must be completely neutralized,” Colombian Defense Minister Pedro Sánchez wrote on X on Friday.
