Updated

A 64-year-old man is presumed dead after he disappeared during a dive at the famed SS Andrea Doria shipwreck off the coast of Massachusetts. Officials say a fellow diver was with the man, who has not been identified, at a 20-foot decompression stop on Tuesday near the spot where the Italian luxury liner went down on July 26, 1956, report CNN and WCVB.

When the witness reached the surface, however, the man was nowhere to be found. A commercial diving boat reported the incident to the Coast Guard, which was on the scene within three minutes, reports the Boston Globe.

The Coast Guard last night called off the search for the missing man after scouring some 350 square nautical miles by air and sea over 30 hours.

The Andrea Doria, known as "the Mount Everest of wreck diving," per ScubaDiving.com, lies 240 feet underwater some 60 nautical miles southeast of Nantucket. It's a popular attraction for advanced divers, but officials note recreational divers shouldn't attempt a visit.

Seven people have died and four have been injured while diving there since 2005. In addition to the deep waters that preserve the 697-foot vessel—which took at least 46 lives when it collided with the Stockholm almost exactly 59 years ago—the wreck itself poses a risk to divers as sections of it have been known to collapse.

On top of that, "here in New England, water temperatures are especially cold and there are strong currents, especially around our shores and islands," says a Coast Guard search and rescue specialist.

(A "mystery" wreck has been found off North Carolina.)

This article originally appeared on Newser: 'Mt. Everest of Wreck Diving' Claims Another Victim

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