A nearby resident says he heard a "tremendous explosion and saw a huge plume of white vapor."
Two people were being treated at hospitals. One - an employee who was reportedly mixing the chemicals that caused the explosion - was listed in critical condition. The second employee was being decontaminated and was expected to be OK.
All employees of the business had been accounted for. Firefighters entered the building to continue their effrtos around 9:45 a.m.
