Police have arrested a suspect they believe opened fire from a rooftop onto the Highland Park Independence Day parade, leaving at least six people dead and roughly two dozen others "seriously injured" Monday.
Robert "Bobby" E. Crimo, III, 22, was taken into custody "without incident" after a brief police chase that ended in Lake Forest Monday evening.
Earlier in the investigation, the gunman was described by Highland Park police as a white man between 18 and 20 years old with a small build and "longer" black hair. He is wearing a white or blue T-shirt, according to Highland Park Police Cmdr. Chris O'Neill.
"We're asking everybody to stay indoors," said Lake County Sgt. Christopher Covelli. "Stay vigilant right now. This person has not been identified. By all means, at this point, this appears to be completely random."
Covelli said the gunman shot into the parade with a high-powered rifle from a rooftop. He said police are working to locate the man.
"All indications is he was discreet, and he was very difficult to see," Covelli said.
In separate social media videos, several gunshots could be heard, followed by a pause and another round of gunfire. In some videos, more than 50 shots are heard.
"Investigators are very, very quickly working to try to identify who this person is, and try to figure out where he's at," Covelli said.
Anyone with photos or video of the incident is being asked to turn them in to police.
"We're asking anybody with any video surveillance that they may have, please review your cellphones," Covelli said. "If you were snapping pictures in the area of Second and Central today, that could help investigators. They may see something in there that may be useful and allow them to proceed further with the investigation. Any business owners in that area we're asking, please, review your video surveillance. If you have any video surveillance of that area at that time, even if you don't see anything in there, we would love to be able to take a look at that so we can further our investigation."
In addition, everyone in the Highland Park area is being asked to report suspicious activity by calling 911 or the Highland Park Police Department at 847-432-7730. The FBI also has established a tip line at 800-CALL-FBI.
Officials urged residents to continue to "shelter in place" even hours after the shooting.
The shooting happened at 10:14 a.m. in downtown Highland Park during the city's Fourth of July parade, authorities said.
NorthShore Highland Park Hospital said in a statement that the facility is treating 26 people, five of whom were transported to NorthShore Evanston Hospital.
"A vast majority suffered gunshot wounds and the remaining sustained injuries as a result of the ensuing chaos at the parade," NorthShore Highland Park Hospital said.
"We mobilized quickly and within 30 minutes of the event had 20 additional physicians (surgeons, trauma surgeons, orthopaedic specialists, etc.) and nurses and other support staff present. We have both crisis and social workers available on-site to assist with family and friends of the individuals injured."
Dr. David Baum, who attended the parade, helped treat those who were injured in the shooting.
"The bodies that I saw, it was not an image that anyone who's not a physician would have an easy time processing," said Dr. Baum.
"There were people who were immediately killed with horrific gunshot wounds."
A large police presence from the state and neighboring suburban Chicago departments was seen along the parade route.
Photos: Images of Scene After Gunfire Erupts During Highland Park Independence Day Parade
"This is an active incident," the city of Highland Park wrote in a statement. "All individuals are advised to shelter in place. Law enforcement agencies are searching for the suspect; evidence of a firearm has been recovered. Numerous law enforcement officers are responding and have secured a perimeter around downtown Highland Park."
"Due to a tragic mass shooting that took place earlier this morning in Highland Park, the City of Evanston will be canceling this year’s 4th of July Parade and celebrations effective immediately."
Larry Bloom, who was in the area when shots began, said at first spectators thought the "popping" sound was part of the parade.
"You heard like a 'pop, pop, pop,' and I think everybody kinda thought maybe it was a display on one of the floats and then it just opened up," Bloom said.
"I was screaming and people were screaming," Bloom said. "They were panicking and they were just scattering and I, you know, we didn't know. You know, it was right on top of us."
The public is being asked to avoid downtown Highland Park as police continue to respond to the shooting "in the area of the Independence Day parade route," the Lake County Sheriff posted on Twitter.
"STAY OUT OF THE AREA - allow law-enforcement and first responders to do their work," the sheriff posted.
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