A suspected Los Zetas boss arrested by the army last week was behind a massacre in the northern Mexican state of Nuevo Leon and led the drug cartel’s push in 2008 into Guatemala, battling rival criminal organizations, a Defense Secretariat official said Monday.

Daniel Elizondo Ramirez, who was arrested on May 18, was paraded before the press Monday in Mexico City.

Elizondo Ramirez “belonged to a group of hitmen led by (Miguel Angel) Treviño Morales who entered Zacapa province, in Guatemala, to expand the organization’s control in that country,” general staff deputy operations chief Gen. Edgar Luis Villegas Melendez said.