NEW ROCHELLE, N.Y. â€"  A New York man died in a bizarre case of delayed drowning -- succumbing a number of hours after pulling himself from the waters of Long Island Sound.

Tommy Mollo, 60, was helping a friend move his boat in a marina at New Rochelle when he fell in the water Saturday morning, WABC-TV reported. After returning to his home in nearby Yonkers, he told his wife he felt unwell and she called 911.

Emergency workers took Mollo to the hospital, where he died.

The cause of death was secondary drowning, with water that got in Mollo's lungs when he fell into the Sound believed to have exacerbated existing health issues.

Gabe Wilson, from St. Luke's-Roosevelt Hospital in New York City, said, "Conceivably water could be inhaled while one still had the means to pull themselves out, but it would certainly be a rare occurrence as usually panic sets in by then."

Larry Baraff, from the Ronald Reagan UCLA Medical Center, said it was possible in Mollo's case that "the drowning episode and lack of oxygen led to a heart problem, like a cardiac arrhythmia or a [heart attack]."

But he conceded, "If you make it to the hospital alive, it's very unusual to die from drowning."

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