DELAWARE, Ohio (AP) — Fire officials in central Ohio say five workers have been injured in a foundry explosion.

Officials say the fire at Liberty Casting Company, in Delaware, was already extinguished when crews responded around 10 p.m. Tuesday.

City of Delaware Fire Chief John Donahue said Wednesday that four people were taken to Ohio State University Wexner Medical Center in Columbus. He says another was taken to OhioHealth Grady Memorial Hospital in Delaware and later released. Donahue says the workers suffered burns, but the conditions of the other four workers weren't known.

Liberty Casting declined to comment. The company's website said it specializes in "gray, ductile and high alloy iron casting."

Donahue says the cause of the explosion remains under investigation.

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