Police said at least five people were killed and 19 were taken to hospital after a shooting at a parade on July 4 in the suburbs of Chicago.
Shooting at Highland Park disrupted the annual parade shortly after it began at 10 am.
It was unclear if the five dead were one of the 19 hospitalized.
Police said authorities were still searching for the suspect, calling it an active case.
The Chicago Sun-Timesreported that the parade started around 10 am but suddenly stopped 10 minutes after firing. A reporter at Sun-Timessaw a blanket resting on three bloody bodies. Several witnesses said they heard gunshots in the newspaper.
Hundreds of parade participants (some visibly bloody) escaped from the parade route, leaving behind chairs, strollers and blankets.
Police told people: "Please disperse everyone. It's not safe to be here."
A video taken by a Sun Times journalist after a gunshot. Shows that the float band continues to play as people scream and pass by. Photos posted on social media seemed to show blood pools near the upward-facing chairs in downtown Highland Park.
Gina Troiani and her son are in his day care class ready to walk on the parade route until they hear people yelling about the shooter when they hear a loud noise that they believe is fireworks. It was lined up.
"We just start running in the opposite direction," she told The Associated Press.
Her five-year-old son was riding a bicycle decorated with curled red and blue ribbons. He and the other children in the group had a small American flag. The city said on its website that the festival would include a parade of children's bicycles and pets.
Troiani said he pushed his son's bike and ran through the neighborhood and back into the car.
In a video taken by Troiani on her phone, some of the children are visibly surprised by the loud noise, and when the siren screams nearby, it scrambles to the side of the road.
It was a kind of confusion, "she said. "There were people looking for them and away from their families. Others dropped the wagons, grabbed the children and started running."
Illinois Governor J.B.Pritzker tweeted "We are closely monitoring the situation at Highland Park," he said, with the support of the Illinois State Police. The ISP said in an email that it was helping respond to active shooters reported around 10:24 am.
The Lake County Sheriff's Office said on Twitter that it was supporting the Highland Park police. The sheriff's office instructed the AP reporter to contact the Highland Park police. Police said no one could comment immediately.
Highland Park resident Debbie Glickman turns to the main route when she sees people running from the area on a parade float with her colleagues. I was preparing.
"People started to say:'There is a shooter, there is a shooter, there is a shooter,'" Glickman told the relevant pres ss. "So we just ran. We just ran. It's like a mess over there."
She's the one who hears noise and looks injured I didn't see it.
"I'm very surprised," she said. "I'm very sad."