"It's just tragic, based on the guns that are on the streets, that three young men have lost their lives today," Chicago Police Superintendent Jody Weis said during a Friday afternoon press conference.
Weis said the victims, all males, were attacked by several individuals and shot with assault rifles, based on cartidges that remained on the scene.
Two cameras in the area were well-positioned to capture the attack, Weis said.
"We're bringing out every resource we can, and we'll work this case as hard as we can," Weis said.
The victims were 13, 14 and 17 years old, Weis said.
The intersection is the same one where a 10-year-old girl was shot and killed last year.
Nequeil Fowler was gunned down while walking with her blind sister, Valerie, on Labor Day.
Four men, all in their 20s, have been charged in that shooting.