Several people were shot in a park on Chicago's South Side Thursday night, police said.
Police could not immediately confirm a report on a Chicago Tribune blog that as many as 12 people had been shot, including a 3-year-old child.
Chicago has been torn by gun violence in recent years, racking up more than 500 murders in 2012, according to a report this week by the FBI.
(Read more: Obama seeks assault gun ban, background checks)
By comparison, New York City, which has a population three times the size of Chicago, recorded 419 murders in 2012, the FBI said.
Chicago police officer Amina Greer told Reuters the shootings occurred at about 10:15 p.m. local time (0315 GMT). There were no immediate reports of fatalities, Greer said, and no one was in custody.
The Tribune blog reported that the shootings appeared to have taken place at a basketball court. Injured people, the newspaper said, were being carried out of the park on stretchers.