MILFORD, Del. (AP) — Authorities are investigating the discovery of a military explosive that prompted the evacuation of a Delaware seafood plant.

The device was discovered Friday morning at the Sea Watch International plant. Some employees were evaluated at a hospital as a precaution, but a Seawatch official said none was sickened

Seawatch chief financial officer Jerry Gordon also said it did not appear that the device contained mustard gas.

But an explosive ordnance disposal unit from Dover Air Force Base responded to the scene, and military officials said the round tested positive for a chemical agent, which Army technical experts will work to identify.

Several years ago, scores of unexploded shells found mixed in with crushed clamshells used to pave driveways and parking lots in
Delaware and Maryland’s Eastern Shore were traced to loads of clams dredged from the ocean floor and delivered to the Milford plant.

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