FORT PIERCE, Fla. (CBS12) — A treasure hunter’s underwater find turned out to be an active explosive, prompting a response from bomb technicians at a Fort Pierce fire station on Monday afternoon.

The Fort Pierce Police Department said its officers responded at approximately 1:10 p.m. July 20 to St. Lucie County Fire District Station 2, located at 855 Seaway Drive, after receiving a report of a found explosive.

According to police, an adult man brought the item to the fire station after discovering it while treasure hunting about one mile east of the Fort Pierce Inlet in about 30 to 40 feet of water.

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The St. Lucie County Sheriff’s Office Explosive Ordnance Disposal Team responded to the scene and determined the item was a live mortar.

The EOD team took possession of the mortar and removed it for disposal. No injuries were reported, according to FPPD.