[1] It was after he was released from prison that he supposedly contacted the Castaño brothers so that he could "buy a franchise" from the powerful AUC paramilitary organization, which allowed him to exert control over a large extension of lands in the Eastern Plains.
[4] He also extended his criminal emporium to Bogotá, where by way of the Capital Bloc of the AUC, which he founded and commanded, he controlled a portion of the trade occurring in the traditional “sanandresitos” (old shopping malls where smuggled items and appliances can be bought).
[2][5] Arroyave also started at some point a bloody war against the Autodefensas Campesinas de Casanare (ACC), a powerful paramilitary group commanded by Héctor Germán Buitrago (aka Martín Llanos) operating on the same territory.
[1][2][4] Following this bloody feud, which left about 3,000 fatalities, Arroyave became paranoid and suspicious of everyone and began spying on his own men and even ordered some killed, which brought fear and hatred among his troops and has been mentioned as the reason why he was later murdered.
[6] The government's chief negotiator, High Commissioner for Peace Luis Carlos Restrepo Ramírez, explained that Arroyave had gone back to the department of Meta to organize the immediate demobilization of his forces.
Another possibility, favored by army intelligence, is that Arroyave was assassinated by a hit squad from the main left-wing guerrilla organization, the Revolutionary Armed Forces of Colombia (FARC).
The AUC leadership, however, laid the blame on a rival within Arroyave's very own Centauros organization:[7] they named Pedro Oliveiro Guerrero Castillo (aka "Cuchillo") as the killer,[8] and described him and his associates as "enemies of peace and opponents of the demobilization process in the eastern plains".