Illinois explosion
© Emily LaughlinA blast rocked a neighborhood Friday night in Lake County, Illinois, where authorities were trying to determine what caused it.
Four people were hospitalized and three are missing after a "ground-shaking" explosion and fire broke out Friday night in an industrial complex in Lake County, Illinois.

Shortly before 10 p.m. the Lake County Sheriff's Department said it was working to determine the cause of a blast in the Gurnee-Waukegan area.

Waukegan Police Commander Joe Florip said four workers were transported to the hospital from the scene with "moderate injuries" as crews continued to actively search the rubble for any other victims.

Police have confirmed that the explosion took place at AB Specialty Silicones, a manufacturing and distribution company specializing in silicone-based ingredients.

Hours after the initial blast, crews continued to fight the blaze and urged residents to stay clear of the scene.


Waukegan Fire Marshal Steven Lenzi said authorities determined that nine people had been in the building at the time of the explosion. Three employees were still unaccounted for as of Saturday morning.

Authorities said at a Saturday morning press conference that the explosion and ensuing fire had left the building too unstable for crews to continue the search.

"Our thoughts and prayers go out to the family and friends of all involved in this horrific incident," Lenzi said in a statement. "Our personnel worked tirelessly through the night to control this scene with help from many neighboring agencies. This was a very large-scale team effort."

Lenzi said at least five other buildings in the area have also been damaged.

Hazardous materials technicians became involved as scene conditions worsened and other products from the plant caught on fire, the fire marshal said. Representatives from Illinois Environmental Protection Agency were also on the scene.

The explosion happened near the Gurnee-Waukegan border, which is about 35 miles north of Chicago.

"Something exploded," resident Emily Laughlin told NBC Chicago. "It looked like it was a building but they stopped everyone from getting closer."

Others in the area posted photos and video of the blast online and described it as a "sonic boom."

Some as far away as southern Wisconsin reported feeling the explosion, the station reported. Power was knocked out to nearly 1,000 residents and windows were shattered across the area.