Eleven other people were taken to hospitals, two of them in critical condition, and about a dozen people were treated at the scene.



"It was a horrific scene," said Oak Lawn Division Police Chief Randy Palmer. "It reminded me as if a bomb had went off somewhere."



Oak Lawn Fire Chief George Sheets said emergency crews found victims "in and around and under cars" like a "stage of a movie set because it was such a violent crash."



"A lot of us here are seasoned veterans," Sheets said at a news conference Monday morning. "This is the most violent and bizarre incident we have seen in our 30-plus-year careers."



Palmer said police were still retracing Carthans' movements before the accident and trying to get a better idea if he had any medical conditions. The person who offered to help did not detect any signs of alcohol, he said.



Carthans had a clean driving record, according to the Secretary of State's office. He last renewed his driver's license in 2011 and was due to renew it in 2015. He lived in the 11000 block of South Morgan Street in the Morgan Park neighborhood on the Far South Side.