A military explosives team has detonated a suspected mine that a diver discovered partially buried in the sand in the ocean off Bay Head but several problems remain.

A World War II era mine is detonated off Bay Head (News 12 New Jersey)

A plume of water shot about 125 feet in the air, and a boom echoed through Bay Head on Wednesday morning.

Borough Beach Manager Hank Handschen says the explosion sheared off the top of the mine and the bottom is still stuck in the muck under the surf and now has jagged edges making for less concern about an unexpected detonation and more of a swimming hazard.

Navy divers are now trying to find a way to pull it out of the sea bed. Hank estimates that it’s about three feet in diameter and extraordinarily heavy. He’s been told that it had the capacity to hold about 600 pounds of explosives.

Handschen tells us the explosive was spotted Tuesday. "I got a phone call yesterday from one of the guards," he said, "he spotted this World War II mine down in the water near Johnson Street about 5 o'clock."

Handschen says that witnesses weren't entirely sure what it was at first, because it wasn't totally visible about 20 yards offshore. "It was pretty much submerged, there was just a little part of it exposed," he says.

The Navy plan is to detonate it, but Handschen says even they're not sure if it will work the first time. If not, they'll have to wire it up for explosion again - and the beach will stay off-limits until they succeed.

The Associated Press contributed to this report