Live Updates: Highland Park Shooting at 4th of July Parade in Illinois

Law enforcement searches a building after a shooting at the Highland Park Independence Day Parade in Illinois on July 4 (named Y. Huh / AP)

Chris Coveli of the Sergeant Lake County Major Crime Task Force said the investigation is still ongoing and will remain active while law enforcement officers work to find the alleged shooter and uncover what happened.

“It’s two-pronged at the moment – number one, we are aggressively looking for the person who is responsible for this shooting. Number two, we have the criminal investigation that is happening simultaneously,” he said.

“It’s very active and it’s going to be very active for a long time to come,” Covelli said.

He said police were working with the FBI and more than 100 law enforcement officers were at the scene. He urged people to check their phones and see if they have any photos or videos from the time the shoots started. He said that any material can help the police.

“Please understand that we cannot divulge certain aspects of the investigation, we do not want negative influence. We want to arrest the perpetrator and hold him accountable for his actions,” Kovelli told a news conference on Monday. “

CMD. Chris O’Neill of Highland Park Police said the rifle they found was found on the roof. Earlier on Monday, officials said they could not say specifically where the rifle was found. Police say they believe the shooter appears to have opened fire from the roof.