The young woman killed by a shark off a remote NSW beach has been identified as a Swiss tourist who was reportedly filming dolphins with her boyfriend just before the attack.

The woman, believed to have been 25, and the 26 year-old-man were bitten while swimming at Kylies Beach in the Crowdy Bay National Park on the NSW mid-north coast on Thursday morning.

By the time paramedics arrived, the woman was dead. But authorities have credited the efforts of another beachgoer with saving the life of her companion, who is also from Switzerland.

He was taken to John Hunter Hospital in Newcastle with severe thigh and leg injuries, and is now in a serious but stable condition.

Several media outlets have reported that the couple were filming dolphins with a GoPro while they were swimming. Police are now reviewing footage from the camera.

NSW Ambulance Mid North Coast Inspector Kirran Mowbray told the Daily Telegraph that the shark initially attacked the woman and was fought off by her partner, who dragged her to shore.

Both he and NSW Ambulance Superintendent Josh Smyth praised the actions of a passerby who called emergency services and applied a makeshift tourniquet to the man’s leg to stem his bleeding.

“He suffered severe injuries to his right thigh,’ Mowbray said. “Our call takers were able to talk the bystander through how to make a tourniquet.”

Smyth said the courage shown by beachgoer was amazing.

“To put yourself out there is very heroic, and it did give us time to get that male patient,” he said.

The Swiss government confirmed the victims’ nationality, and its foreign affairs department said it was supporting their families.

The ABC is reporting that police are working with the Department of Primary Industries using drones to look for a bull shark which is believed to be responsible for the attack.

The beach has been closed since incident at 6.30am on Thursday.

Five SMART drumlines would be temporarily installed off Kylies Beach, the NSW government said. They are already in place to the north at Port Macquarie and to the south at Forster.

The national park, about an hour’s drive south of Port Macquarie, is known for beach camping, fishing spots and walking tracks.

Port Macquarie MP Robert Dwyer said the local community was heartbroken.

“I want to thank the people who stepped in straight away and the first responders who pushed through tough conditions to do everything they could,” he said.

Surf Life Saving NSW chief executive Steven Pearce said the “really, really terrible” incident had occurred at a particularly remote part of the national park.

“These incidents are horrific for everyone and unfortunately we’ve had a few this year already,” he told 2GB radio.

“It’s so remote there’s no life guarding services up there.”

It is the second fatal shark attack in NSW in two months.

Shark attack victim Mercury Psillakis.

In September, avid surfer Mercury Psillakis, 57, was killed by a great white shark at Long Reef Beach in northern Sydney. He had warned other surfers about the shark before he was fatally mauled.

It prompted the state government to scrap a trial removal of shark nets at three NSW beaches, with Premier Chris Minns suggesting it would be “silly” to push on with the plan.

Researchers and animal advocates have long argued the nets – used between Newcastle and Wollongong – offer minimal protection and predominantly injure other sea life.

SMART drumlines, in which sharks are tagged, released and then monitored, have been increasingly used since being introduced in NSW a decade ago.

-with AAP