Questions about ranks of FARC hostages

What's a "Patrullero", "Agente" and "Intendente"? I think that a "Professional Soldier" is basically a Private. In June 2001 and February 2009, the FARC released all the Patrulleros, Agentes and Professional Soldiers but they kept an Intendente named Alvaro Moreno. Are Patrulleros and Agente's lower ranking officers?