SIOUX FALLS, S.D. (AP) — The death of a Minnehaha County dive team member during a training exercise has been ruled accidental.

The Argus Leader reports the death certificate for 43-year-old Jeff Thumma states he died from a lack of oxygen to the brain that could have been complicated by a heart condition.

Thumma was an experienced diver. He was taking part in a training exercise July 10 at a Sioux Falls park when he tugged at a safety rope four times to signal an emergency. It took only about two minutes for rescuers to pull Thumma from the water, but he was unresponsive and died after several days on life support.

Police spokesman Sam Clemens says Thumma's diving equipment was tested and found to be fully functional at the time of the incident.

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