The Lake County Sheriff reports the explosion came from the AB Specialty Silicones plant in the area near Sunset Avenue and Northwestern Avenue in Waukegan. The sheriff is asking people to stay away from the area, but no evacuation order has been put in place as of 10:45 p.m.
According to the City of Waukegan Fire Marshal Steven Lenzi, the explosion happened around 9:30 p.m. Friday.
Four people have been taken to the hospital with unknown injured. Two other at the scene did not need treatment.
After talking to plant personnel, officials say they determined there were nine people inside the building at the time of the explosion, three are still unaccounted for as of 8:00 a.m. Saturday.
Officials say they suspended the search for the missing workers due to structural instability and chemical concerns and will now focusing on search and recovery.
The names of the three missing individuals have not been released at this time.
WATCH: Photos of the aftermath of the explosion in Waukegan
Video from social media shows the aftermath of the explosion and fire. Many of the initial reports of the incident came from Gurnee, where residents said they heard the explosion and felt their homes shake.
The aftermath of the explosion also clearly shows smoke and fire. People across Lake County reported hearing and feeling the blast.
You can hear the factory plant explosion in this.. just happened a few minutes ago in Gurnee.. pic.twitter.com/VAIC9pE7FI— BL🌸🌸M (@leeblooms) May 4, 2019
A witness said that while she was driving down Delany she heard a large boom and saw debris flying through the air. When she turned onto Sunset Avenue, she saw more insulation and debris in the air and then saw a second boom.
Sand has been put out to stop hazardous material form the plant from getting into the already swollen river.
Nearby roads are impassible until further notice due to concrete and metal debris in the roadway. Five other building nearby were also damaged.
More than 100,000 gallons of water was used to put out the fire. Officials say they are now dealing with whatever contaminants may now be in the water that was used to put out the fire.
30 different departments and over 100 firefighters from as far as Wisconsin responded to the scene according to Lenzi.
The Illinois State Fire Marshal and the Occupational Safety and Health Administration (OSHA) are investigating what may have cause the accident.
Lenzi said the building has sustained 90 percent or more damage, with damage estimates exceeding at least a million dollars.