The suspect, a nephew of extradited paramilitary leader Hernan Giraldo alias “El Viejo,” was arrested on charges of homicide, forced displacement and conspiracy.
Ruben Giraldo and allegedly other members of the same family, formed a militia last year to push the Urabeños out of Santa Marta and the nearby Montes de Maria region that used to be controlled by his uncle.
The fighting has left dozens dead over the past year.
According to the Colombian Police’s counter-narcotics unit, Giraldo and his group transports cocaine from the Caribbean coast to Central America using go-fast boats.
Giraldo was arrested in Santa Marta last year on illegal weapons charges, but was released after charges wouldn’t stick. The alleged crime lord then moved to the capital to evade local authorities.
“El Viejo” was one of the top commanders of the now-demobilized AUC. The former paramilitary commander is accused of having sexually molested dozens of minors.