WATCH: The unbelievable moment a school of 100 hammerhead sharks swim near divers

Ric Morgan captured the amazing footage on a head-mounted GoPro camera while diving at Fish Rock Cave in South West Rocks, New South Wales on Monday October 30.

The 66-year-old, a dive master with South West Rocks Dive Centre, said the rarely-witnessed phenomenon was a “once in a lifetime experience” as there are only a handful of locations worldwide where the animals congregate in such large numbers.

He said while the predators knew he and the 12 other scuba divers present were there, they did not alter their behaviour as they swam past and he did not feel threatened.

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