MELBOURNE, Australia: A woman was killed and a man seriously injured when a shark attacked them during an early morning swim at a national park beach on Australia's east coast on November 27, police said.

A shark rarely attacks more than one person, experts say.

Crowdy Bay National Park, near Port Macquarie in New South Wales — known for beach camping, fishing spots, and hiking tracks — 224 miles north of Sydney, was the scene of the attack.

The victims were Swiss nationals. "The Swiss Consulate General in Sydney is in contact with the local authorities and is supporting the relatives within the framework of consular protection," the Swiss Federal Department of Foreign Affairs said in a statement.

Police Chief Inspector Timothy Bayly said swimmers were indefinitely barred from entering beaches in the area and to the north after the attack.

Bayly said emergency services were rushed to Kylies Beach at 6:30 a.m. following reports that a shark had attacked two people in their mid-20s.

Bayly provided no details of the injuries or the attack. "At this stage, all I'm prepared to say is they were known to each other, and they were going for a swim, and the shark attacked," Bayly told reporters.

A bystander offered first aid but could not prevent the woman from succumbing to her injuries before ambulance paramedics arrived.

Paramedic Josh Smyth said a helicopter flew the man, whose condition was serious but stable, to a hospital.

"I just really need to have a shoutout to the bystander on the beach who put a makeshift tourniquet on the male's leg, which obviously potentially saved his life and allowed New South Wales Ambulance paramedics to get to him and render first aid," Smyth told reporters.

The identities of the man and woman were not released.

The government said five drumlines, which are baited hooks suspended from floats, were deployed off Kylies Beach in an attempt to catch the shark.

Gavin Naylor, director of the University of Florida's shark research program and manager of the International Shark Attack File database, said a single shark attacking more than one person was exceptionally rare.

A shark attacked two British tourists while they were snorkeling on the Great Barrier Reef off Australia's northeast coast in 2019. One lost a foot, and the other suffered injuries to his leg.

In September this year, a shark fatally mauled a surfer off a Sydney beach. Only two sections of his surfboard were recovered.