Illinois police have taken a 'person of interest' into custody after a mass shooting left six people dead and several others wounded.
Police attempted to stop Robert E. Crimo III during a traffic stop, however he allegedly took off.
He was apprehended a short time later and will be taken to the police department in Highland Park, according to CNN.
The news outlet added that police have not stated Crimo is a suspect in the shooting, and has been labelled a 'person of interest' instead.
Highland Park Police Chief Lou Jogmen said Crimo will be questioned 'to make sure or see if, in fact, he is connected to this incident'.
A police press conference revealed the gunman used a 'high-powered rifle' in the hope of inflicting as much damage as possible.
Perched on a rooftop, the shooter opened fire on people down below who had gathered for fourth of July celebrations in Highland Park.
Witness Zoe Pawelczak said everyone thought the gunshots were just fireworks.
"And I was like, something's wrong. I grabbed my dad and started running," she revealed to CNN.
"All of a sudden everyone behind us started running. I looked back probably 20 feet away from me. I saw a girl shot and killed."
Miles Zaremski told NPR: "I saw the carnage, and I almost broke down."
He added: "It's surreal. It must have been a science fiction film I just saw, but unfortunately it wasn't," he said. "Our country is a scary place."
Christopher Covelli, spokesperson for the Lake County Major Crime Task Force, said the gunman used a ladder attached to the building to reach his position.
The people who were injured in the shooting ranged in age from 8 years old to 85.
CNN added that 19 of the 25 gunshot victims have since been treated and discharged from hospital.
Governor JB Pritzker – the 43rd governor of Illinois – tweeted: "My staff and I are closely monitoring the situation in Highland Park. State police are on the scene and we have made all state resources available to the community.
"We will continue working with local officials to help those affected."
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