The unnamed man, aged 60, who is said to have been a certified diver, was found unresponsive on the ocean bed while diving on Agincourt Reef north of Cairns, the Daily Mirror reports. Attempts to revive him with a defibrillator were unsuccessful.
Earlier this week, two French tourists aged 76 and 74 were found floating in the water at Michaelmas Cay within minutes of each other. They are both believed to have suffered heart attacks.