The woman, named in the Sydney Morning Herald as Chantelle Doyle, 35, was rushed to Port Macquarie Base Hospital with serious leg injuries after she was mauled off Shelly Beach about 9.30am on August 15.

Her husband Mark Rapley came to the rescue, jumping on the shark and punching it repeatedly until it let her go before he placed her on his board and rushed to shore where bystanders rendered assistance until emergency services arrived.

"The shark was latched on to her leg. I just jumped into the water," he told the media, visibly shaken by the incident.

Mr Rapley said the shark was a "ball of muscle" as he punched down on it numerous times before it released its grip.

Witness Jed Toohey said Mr Rapley put his life at risk to save his partner.

"If he hadn't put his own life at risk, [the shark] would have been strong enough to take her out to sea."

Ms Doyle was later flown to Newcastle's John Hunter Hospital where she underwent surgery.

She is recovering and in a stable condition on Sunday.

NSW Police said she was bitten on the right calf and the back of her thigh.

Surf Life Saving NSW CEO Steve Pearce said Mr Rapley's actions were a "tremendous act of bravery".

"The shark wouldn't release her and so a nearby surfer paddled over and essentially jumped on the shark and started hitting it to make it release," Mr Pearce told AAP.

"We've had some really serious and tragic shark encounters over the past couple of months along the NSW coastline so to paddle out of your own safety zone, in to an area where you know there is a large shark, I think is amazing."

Three Ambulance NSW crews, a specialist medical team via the Westpac Rescue Helicopter along with one inspector were dispatched to the job.

"This is the third serious shark attack on the north coast over the last few months," Inspector Andrew Beverley, duty operations manager for Ambulance NSW, said.

Paramedics were on scene within eight minutes.

"The bystanders on scene that rendered assistance should be commended. They did an amazing job before we arrived," Insp Beverley said.

All beaches in Port Macquarie were closed by ALS Lifeguards and surfing and swimming was not advised.

Surf Life Saving NSW provided coastal surveillance of the area using UAVs (drones), jetskis and inflatable rescue boats (IRBs) to help spot the shark and assist the NSW Department of Primary Industries.

Australian Associated Press

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