Four Shelton firefighters were injured battling the Latex International factory fire, including one with a broken shoulder.
Shelton Fire Chief Fran Jones said the firefighter with the broken shoulder was taken to Bridgeport Hospital for treatment.
The other three firefighters all experienced heat exhaustion, and were treated at the scene and released, he said.
Firefighters from all four of the city’s volunteer fire companies — Echo Hose, Huntington, Pine Rock and White Hills — responded to the late-night fire, Jones said.
They were assisted by fire crews from Ansonia, Derby, Orange and Stratford, with the Monroe and Nichols (Trumbull) departments providing back-up coverage in the city.
The Shelton fire marshal’s office, local HazMat Unit and state environmental crews also were observed at the scene.
All four of the injured firefighters were with Shelton fire companies.