French tourists die from heart attacks on Great Barrier Reef.

Two French tourists have died while snorkelling together at Michaelmas Cay on the Great Barrier Reef, in waters off Cairns.

The pair, believed to be in their 60s, suffered heart attacks while on a snorkelling tour of the reef on a Passions of Paradise boat.

A spokeswoman for the company said it was believed the tourists had pre-existing medical conditions.

More to come.

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