"Crushing blow against [the National Liberation Army] ELN as Resistance Front ringleader Cimarron [killed]… Alias ‘Franklin’ top leader Cimarron of the ELN Resistance Front was responsible for financing and partly arming the front structures," the Military Forces of Colombia tweeted.
The military added that Franklin's killing "represents a blow against ELN because it is not easy to replace him with someone to continue the activities of this terrorist."
Franklin reportedly fought alongside the second-largest rebel group after the Revolutionary Armed Forces of Colombia (FARC) for 25 years.
Among other accusations, he is claimed to have killed and kidnapped people, as well as control drug trafficking from the Choco province. He reportedly displaced the Clan Ususga gang from the province’s Baudo and Bahia Solano municipalities.