Detectives wrapped up their preliminary investigation late Sunday night, but earlier there was a heavy police presence, combing the area for evidence, interviewing residents in the area.
Police say there were four children that were injured in the shooting, including three girls and one boy, all between the ages of 11 and 15 years old.
Witnesses say the shooting appears to have stemmed from an argument that started between a group of girls at a playground a half a block from the shooting. Several minutes later, the argument ended up on the street at Michigan and Marquette where the shooting took place.
Police say the shots were fired from a moving vehicle. No arrests have been made.
Witnesses say this is not the first time that an argument that began in the park has ended up in a shooting.
"Sometimes I don't want my nieces and nephews to come to the park because if one little girl is fighting, and then her brother or her cousin that's gang-affiliated, then it's that, then it's this, then it's shooting," said Radriana Polk.
The Chicago Fire Department said that two of the injured were taken in serious condition, the other two in critical. Two are at Comer Children's Hospital and the other two are at Cook County Hospital.
Indications appear to be that the shooting was gang related.