Authorities say seven workers suffered burns when an explosion occurred at an ink manufacturing plant in northern New Jersey.

Explosion at U.S. Ink plant in East Rutherford (Image courtesy of WABC-TV)

Workers at the U.S. Ink plant in East Rutherford were mixing newspaper ink in a vat when a carbon compound apparently ignited around 1:15 p.m. Tuesday, sparking an explosion and a fire in the building's ductwork. Plant workers tried unsuccessfully to extinguish the blaze, which was soon contained by borough firefighters.

At least one injured worker was being treated at a hospital, but most were treated at the scene. None of the injuries are considered life-threatening.

The cause of the explosion remains under investigation, but officials say it doesn't appear that the workers are at fault.

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