Two men charged in Back of the Yards shooting [UPDATE] 23 (UPI) -- Two young men were charged late Monday in Chicago's Back of the Yards shooting that left 13 people wounded, authorities said. Bryon Champ, 21, and Kewane Gatewood, 20, are each charged with three counts of attempted murder and three counts of aggravated battery with a firearm in the Thursday night mass shooting at Cornell Square Park on Chicago's South Side, the Chicago Sun-Times reported. The newspaper's sources said the attack was to avenge the wounding of a gang member several hours earlier. Police have said some of the victims in the park shooting are members of the Gangster Disciples and the shooters are suspected of being associated with the Black P Stones. The Sun-Times said Champ has previous convictions for weapons and stolen property charges. The men were arrested during the weekend in an abandoned building, police said. A "military grade" weapon was used in the park shooting, Police Superintendent Garry McCarthy said. The wounded included 3-year-old Deonta Howard, who was shot in the head. He was expected to recover but would require plastic surgery, family members said.