CHICAGO (AP) - Two men have been charged in a mass shooting at a Chicago park that wounded 13 people, including a 3-year-old boy, but neither suspect is believed to have been a triggerman, according to police. Byron Champ, 21, and Kewane Gatewood, 20, are charged with attempted murder and aggravated battery with a firearm in the shooting Thursday night at Cornell Square Park on Chicago's southwest side, police said late Monday. The suspects' home towns were not revealed. Authorities have said as many as three people opened fire on a basketball court in the Back of the Yards neighborhood. Among the injured were 3-year-old Deonta Howard, who is recovering from surgery after being shot near an ear, along with two teenagers. Chicago Police Superintendent Garry McCarthy said Monday night in a statement that while the men played significant roles in the shooting, neither man was believed to have been a gunman in the incident. "Chicago Police detectives continue to work tirelessly to solve this case and hold the criminals who committed this senseless act of violence last Thursday night responsible for their actions," McCarthy said in a statement. These charges are just the beginning, and this investigation remains ongoing at this time. Champ has previous weapons charges. He was convicted in July 2012 on charges of unlawful use of a weapon by a felon and sentenced to Cook County Jail's boot camp. Champ is a documented gang member, according to authorities. "To truly address violence for the long-term we need state and federal laws that keep illegal guns out of our communities and provide real punishment for the criminals who use them," McCarthy said. He said the shooting highlighted a need for a three-year mandatory minimum sentence for illegal gun possession and truth in sentencing for gun crimes in Illinois. The shooting returned Chicago's gun violence problem to the nation's consciousness. The assailants fired more than a dozen rounds from an assault-style rifle, police have said. They believe the shooting was gang-related, as several gang members were injured, although it's not yet clear who the intended target was. Mayor Rahm Emanuel rode along with police officers late Sunday in particularly violent city neighborhoods. Emanuel has made curbing violence a high priority, allowing the Police Department to spend millions of dollars in overtime to saturate high-crime areas with hundreds of additional officers. Through Sept. 15, police say, they've recorded 306 murders and 1,402 shooting incidents this year. That's down 20 and 22 percent, respectively, from the same period in 2012. Police say overall violent crime is down about 15 percent, according to new figures released Monday.