Eileen Marco, 73, of South River, was killed at the scene of the explosion at Superior Signal Company, LLC in Old Bridge at approximately 11:20 a.m., Middlesex County Prosecutor Yolanda Ciccone said.
Four other people were injured. Photos from the scene show medical choppers landing at Veteran's Field, located nearby to transport two of the victims with serious injuries. The other two victims were taken to an area hospital with minor injuries, Ciccone said. Foul play was not suspected.
Superior Signal Co. is located across the road from Jonas Salk Middle School where students and staff sheltered in place as a precaution.
Superior Signal's website says it's been providing the industry with smoke generators and ultrasonic leak detectors for more than 60 years.
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