SALVO, N.C. (AP) — Authorities say a 49-year-old Virginia man vacationing on the Outer Banks has died after he was buried in 6 feet of sand while digging a tunnel to connect two large holes.

National Park Service spokeswoman Cyndy Holda said family members and others on the beach tried to dig out David Frasier of Fredericksburg, Virginia, but he was buried too deep.

Holda says rescuers were able to free Frasier at the beach south of Salvo about 15 minutes later, but he was already dead.

Holda says beach sand seems firm when it is wet, but it moves and loosens up as it dries out. She says to stay safe, vacationers shouldn’t dig holes deeper than the knees and fill them at the end of the day.

Holda says its been at least 10 years since anyone has suffocated when sand collapsed.

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