Twelve people, including a 2-year-old, are killed and 16 more injured during a shootout between different factions of the Sinaloa Cartel at El Castillo Penitentiary Centre in Mazatlán, Sinaloa, Mexico. The incident is believed to have been an assassination attempt on Eduardo Jonathan Martínez Larios, a leader of "Los Chapitos" who was reportedly amongst the dead.