The boy was swimming at Rudder Reef when he was mauled by the shark about 11.30am.

It’s understood the victim was a local. It’s not known what kind of shark was involved in the attack.

The boy suffered a serious injury to his thigh and despite others administering CPR and the use of a defibrillator on a boat, he could not be saved.

Veteran diver Col McKenzie, who also heads the Association of Marine Park Tourism Operators, said Rudder Reef was not a common spot for dive tourism operators.

But he said it was popular with spear fishing enthusiasts, and there was a fatal shark attack at nearby Opal Reef almost a decade ago to the day.

Spearfisherman Mark Thompson, 38, died from a heart attack soon after being attacked by a shark December 11, 2004.

St Crispin’s reef separates Opal and Rudder reefs, and there is little distance between them.