Two women have been injured by a 50-foot humpback whale while swimming off the north-west Australian coast.
A mother whale was reportedly protecting her calf when she swam at a group of snorkellers and swung her tail at tourist spot Ningaloo Reef near the town of Exmouth on Saturday.
A 29-year-old woman was struck by the giant mammal’s tail and sustained fractured ribs and internal bleeding, Nine Network television reported.
She was flown to a Perth hospital on Sunday and remained in a serious but stable condition, the WAtoday website reported.
The second swimmer was struck by the same whale's pectoral fin, which tore her hamstring, Nine reported.
The Western Australian state government licenses tour operators and sets conditions including keeping swimmers a safe distance from whales that they observe.
The government's Department of Biodiversity, Conservation and Attractions said it was working closely with the industry and the tour operator involved to understand how the incident occurred.
"Swimming with humpback whales involves some inherent risk," a department statement said.