A World War II-era mine was detonated on Wednesday after a diver discovered it partially buried in the sand in the ocean off a New Jersey Beach.
Water shot about 125 feet in the air and a boom echoed through Bay Head as divers from the Naval Weapons Station Earle blew up the device with a 10-pound charge of C-4 explosives.
The device was believed to be a contact mine from either World War I or World War II, base public affairs officer Michael Brady said. But it was not known whether there were explosives inside or if it was just used for training.
Authorities evacuated about 15 homes and a quarter mile radius as a precaution. The Coast Guard kept boats clear of the area.
The explosive’s team is taking what's left of the mine back to their shop to try to determine what it was and how it ended up at the beach.
Superstorm Sandy may have exposed the device, Brady said. The explosives team has responded a half-dozen times to similar incidents since the storm hit the Jersey shore on Oct. 29, but mainly to the north near Sea Bright and Sandy Hook.
Sandy Hook was used as a military proving ground for explosives between 1874 and 1919.
While startling to some, the discovery of old munitions on Jersey shore beaches or just offshore is not all that unusual. The military has said it dumped large quantities of munitions overboard at the end of both World Wars as the conflicts were ending.
In 2007, more than 1,000 pieces of World War I and World War II-era munitions were discovered on the beaches of Long Beach Island after they were unwittingly sucked up by dredges and pumped ashore as part of a massive beach replenishment project.
Similar discoveries have been made off the coasts of Delaware and New York.
In 2007, the U.S. Army Corps of Engineers recovered 1,080 pieces of material, including fuses and other military hardware, from Surf City and Ship Bottom that were unearthed as part of the beach project.
Merchants rushed to capitalize on the unwanted publicity by selling T-shirts with slogans including, “Our Beaches Will Blow You Away” and “I Got Bombed On Long Beach Island.”