CHICAGO (REUTERS) - Chicago police are searching for suspected gang members who opened fire with an assault weapon at a park late on Thursday, wounding 13 people including a three-year-old boy, in an attack that highlighted Mayor Rahm Emanuel's struggle to stem street crime.
Chicago Police Superintendent Garry McCarthy told a news conference that up to three gunmen used at least one assault-style weapon with a high-capacity ammunition clip to fire on a crowd in the city's Back of the Yards neighbourhood.
The shooting, on a warm night when residents were enjoying a basketball game, came 10 days after Mr Emanuel and Mr McCarthy held a press conference in a nearby neighbourhood to claim success in a strategy of flooding 20 high-crime neighbourhoods with police.
Back of the Yards was not one of the neighbourhoods which received police reinforcements under the plan, Mr McCarthy said on Friday.
He blamed lax gun control laws for allowing assault weapons on the streets and complicating efforts to curb violence in Chicago, which has a worse murder rate than the more populous cities of New York and Los Angeles.
"A military-grade weapon on the streets of Chicago is simply unacceptable," Mr McCarthy said. "This kind of shocks the consciousness just like the other high-profile incidents that happen across this country."
The Chicago shooting followed the killing of 12 people at the Navy Yard in Washington on Monday by a man with a history of gun-related offenses and treatment for mental illness.
Mr Emanuel's office said he cancelled meetings in Washington on Friday and returned to Chicago, where he went to a hospital to visit Deonta Howard, the three-year-old boy police said was critically wounded by a bullet entering his ear.
"Senseless and brazen acts of violence have no place in Chicago and betray all that we stand for," Mr Emanuel said in a statement. "The perpetrators of this crime will be brought to justice and prosecuted to the full extent of the law."
Mr Emanuel, a former White House Chief of Staff for President Barack Obama, promised when he was elected mayor in 2011 to make the streets of Chicago safe for everyone.
According to witnesses, gunfire rang out late on Thursday night as a crowd was watching basketball.
"We were sitting in the park talking, then two dudes came up, stood by the gate for a minute, then they just started shooting," said Michelle Adams, 16.
Other witnesses said the gunmen had driven up and fired on the basketball court from their vehicle.
Police said that besides Howard, those injured ranged in age from 15 to 41.
"It's a miracle there were no fatalities," Mr McCarthy said.
Three of the gunshot victims, including Howard, were in serious to critical condition in area hospitals. Mr McCarthy said none of the injuries were life threatening.
Mr Naphtali Dukes, 38, who identified himself as Howard's cousin, said he had been told that the boy would survive.
Mr Mitchell Gary, 53, said his brother was shot in the back and buttocks and his nephew was shot in the arm and ankle.
"I was walking up the street and all of a sudden I heard gunshots," Mr Gary said. "When I got there, everybody was screaming, then I see my brother and nephew laying on the ground shot."
Gun violence in Chicago led to more than 500 murders in 2012, according to a report this week by the Federal Bureau of Investigation. New York City, with three times Chicago's population, had 419 murders in 2012, the FBI said.
One Chicago murder this year which caught national attention was of Hadiya Pendleton, 15, an honour student killed at a park just days after she performed at a January presidential inauguration event in Washington.
Mr Obama, who considers Chicago his hometown, tried to tighten the nation's gun control laws after 26 people, among them 20 children, died in a shooting rampage last December in Newtown, Connecticut.
The effort failed in Congress after the powerful gun rights lobby, the National Rifle Association, opposed tougher laws.
Chicago and the state of Illinois have loosened some gun laws this year despite the opposition of Mr Emanuel. The city council abolished its registry of gun owners after its gun control law was ruled unconstitutional by the courts. Illinois approved the concealed carrying of guns and is the last state in the nation to authorise some sort of carrying guns in public.
Crime is one of a host of issues confronting Mr Emanuel. Citing budget problems, the city closed 50 public schools in May, angering parents and the teachers union. The city faces large and growing pension liabilities, and Mr Emanuel's former senior finance official was recently indicted in Ohio, sparking an investigation of the official's dealings in Chicago.