Deputy Fire Chief Ron Wolfe said the workers' injuries from the Friday night explosion at the Protecpac building in Sidney were not considered life threatening.

Wolfe said the company uses isobutane to expand plastic in making a foam product used in packaging. He said fire investigators are trying to determine the cause of the explosion. Residents nearby reported hearing a loud noise and feeling their homes shake.

Fire officials were told four people were working in the building at the time. Wolfe said two were taken to Wilson Memorial Hospital, and a third worker declined medical treatment.