RAYMOND, Maine (AP) -- The state medical examiner's office says a diver who died while attempting to retrieve his submerged ATV from Maine's Sebago Lake died from an air embolism and drowning.

The Cumberland County Sheriff's Department says 53-year-old Steven Viola of Gray was attempting to recover the all-terrain vehicle that had crashed through the ice. He was not breathing when he was pulled from the water by his friends Monday afternoon.

An air embolism is characterized by a bubble in the bloodstream and can be caused if a diver attempts to surface too quickly.

The medical examiner says Viola had an air embolism in his heart that caused it to stop pumping. The official cause of death was the embolism, with drowning.

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