Crowdy Bay, Australia - A bull shark killed a woman swimming off a remote beach in Australia’s eastern state of New South Wales Thursday while a man was seriously injured and may have been saved by the "heroic" efforts of a passerby.

The woman died at the scene of the attack, which took place in the early hours of the morning in the remote Crowdy Bay, around 155 miles north of Sydney.

The man suffered serious leg injuries and was airlifted to hospital. Police have said his condition is stable.

"They were known to each other, and they were going for a swim and the shark attacked," New South Wales Police inspector Timothy Bayly told reporters.

A bystander potentially saved the man's life by wrapping a makeshift tourniquet around his leg, state ambulance inspector Joshua Smyth said.

"The courage from some bystanders is amazing in this situation – to put yourself out there is very heroic," he said.

Steven Pearce, Surf Life Saving NSW chief executive, described it as "a really, really terrible incident".

"This area is so remote, there's no life guarding services up there at all," Pearce told local radio 2GB.

Authorities determined a bull shark – one of the deadliest species of the deep-sea predatory fish – was most "likely to have been" involved in the attack.

Increasingly crowded waters and rising ocean temperatures that appear to be swaying sharks' migratory patterns may be contributing to an escalation in attacks despite overfishing depleting some species, scientists say.

In September, a great white mauled a surfer to death at a popular Sydney beach.

The man, who had a wife and young daughter, lost "a number of limbs" and his surfboard was broken in two, police said.

A 40-year-old pastor was killed last December while fishing in the waters of Australia's Great Barrier Reef.

Australia's oceans are teeming with sharks, with great whites topping the list of species that might fatally bite a human. Though still relatively rare, fatal attacks do appear to be on the rise with 56 reported deaths in the 25 years to 2025 compared to 27 deaths in the previous quarter-century.

Authorities have adopted a multipronged approach to protecting swimmers: deploying drones, fixing acoustic trackers to sharks so they can be detected by listening buoys near popular beaches, alerting people in real time with a mobile app, and stringing up old-fashioned nets.

Researchers say shark lives, too, need protecting.

About 37% of oceanic shark and ray species are now listed as either endangered or critically endangered by the International Union for Conservation of Nature, a database for threatened species.