He reportedly began working for the founder of the Oficina de Envigado, Diego Murillo, alias "Don Berna," as an assassin when he was still a teenager, and managed to struggle his way to the top of the Oficina by remaining alive while Murillo’s other associates were killed off or jailed. Following Murillo’s extradition in 2008 and the surrender of Murillo’s successor Carlos Mario Aguilar, alias "Rogelio," Bonilla aggressively expanded the Oficina’s territory into the Guajira, Atlantico and Bolivar provinces, filling the power voids left behind after the demobilization of the United Self-Defense Forces of Colombia (AUC).
In 2008, he seized an important drug corridor through the Uraba region after the extradition of Daniel Rendon Herrera, alias "Don Mario." He gained control of more trafficking routes through Cordoba following the capture of Victor Mejia, who headed up the "Mellizos" organization.
In the months leading up to his capture, Bonilla faced increasing pressure, both from enemies and allies, as some of his associates tried to follow Aguilar to the United States to become co-operating witnesses. In July 2009, his partner, Mauricio Lopez Cardona, alias "Yiyo," turned himself in to Colombian authorities. Another leader of the Oficina, Fabio Leon Velez Correa, alias "Nito," was killed by his own subordinates for seeking a similar deal with US authorities. Bonilla refused to cede power, and the internal feuds within the Oficina grew more aggressive as Bonilla became increasingly paranoid that his associates might be clandestinely negotiating to give him up.
Bonilla was long thought to be hiding on Colombia's Caribbean coast, but was arrested in November 2011 in the city of Maracay, Venezuela. His capture was the result of years of tracking by the Colombian intelligence services, and he was eventually taken into custody on the eve of a visit by President Juan Manuel Santos.
- “International Narcotics Control Strategy Report - 2010,” U.S. Department of State (March 2010)
- U.S. Department of State Narcotics Rewards Program: Maximiliano Bonilla