CHICAGO (CBS) — Two people are confirmed dead and two employees are still missing after an explosion rocked a silicone plant in Waukegan just before 10 p.m. Friday.

The company, AB Specialty Silicones, manufactures and distributes various grades of silicone products.

Employees too shaken up to talk on camera say second shift supervisor Byron Biehn saved lives alerting everyone inside to evacuate after realizing something wasn’t right.

He’s one of the two men still missing. The other is a lab technician who was just hired in September.

At least two were killed in the explosion. One passed away Saturday after more than 12 hours in the burn unit.

Emergency crews suspended their search for the missing employees at 7 p.m. Saturday. They will resume the search Sunday morning.

Officials said it is unlikely the missing people survived the explosion.

Mac Penman, general manager at AB Specialty Silicones released a statement Saturday evening, saying:

“We are shocked and heartbroken by the tragedy that occurred in our plant last night. We have spent the day trying our best to support all of the members of our AB family as we attempt to process this terrible loss together.

We want to express our extreme gratitude to all of the first responders who arrived at the scene. We continue to work closely with the Waukegan Fire Department and the Illinois Fire Marshal as they secure the scene and complete their investigation.”

The fire marshal said officials are working with the site owner to secure the site.

Three other people injured in the explosion are still being treated in area hospitals. Their conditions are not known at this time.

Officials said 9 people were in the building at the time.

Sunset Avenue remains closed between Greenbay Road to Delany Road.

According to officials, the explosion also damaged at least five other buildings in the area and damages are estimated to be in excess of $1,000,000.

“Our thoughts and prayers go out to the family and friends of all involved in this horrific incident, ” Waukegan Fire Marshal Steven Lenzi said in a written 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. We received assistance from numerous fire departments, police departments and our public works crews even assisted at the scene. We had well over 100 personnel working in dangerous conditions and had no major injuries report.”