Cary Police Chief Steven Casstevens said the first report of an explosion in the two-story, brick building at Fox Valley Services came in about 1:15 p.m., and the fire that resulted from the blasts was extinguished by about 5 p.m., the Chicago Tribune reported.
Casstevens said there were at least two explosions that blew the front of the building off and created a small hole at the rear of the building.
The three workers who were injured were hospitalized in unknown condition, but their injuries were not considered life threatening, he said.
The cause of the explosions had not been determined, the Tribune said.
Notable deaths of 2014 [PHOTOS]