An explosion that rocked a silicone factory in the Chicago suburb of Waukegan late Friday has killed one person and injured four. Two people known to be in the plant at the time remain missing. All involved were employees of the AB Specialty Silicones, according to CNN. The explosion shook the town, which is about 40 miles form Chicago. Fire Marshal Steven Lenzi told CNN that the search the missing workers was suspended early Saturday when conditions became too dangerous, calling into question how long the structure would stay standing. Lenzi said the company will bring in heavy lifting equipment to start moving debris.