There was a report of an explosion at about 11:20 a.m. on Wednesday, May 1, Old Bridge police said.
UPDATE: Police ID Worker Killed In Old Bridge Explosion
"There were multiple severe injuries" and two medical helicopters were called to help take victims to hospitals, police said.
Superior Signal Co. is located across the road from Jonas Salk Middle School where students and staff sheltered in place as a precaution.
Old Bridge had assistance from first responders from East Brunswick, Spotswood, Marlboro and Monroe, they said.
It was not yet known how many people were injured, how many went to the hospital or the extent of their injuries.
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