A report from The New Zealand Herald reveals the efforts police went to to save a man taken by a great white off the Auckland coastline. Courtesy: New Zealand Herald

FRIGHTENING footage has emerged of the moment a police officer shot at a shark which mauled a man to death in New Zealand.

Father-of-one Adam Strange, 46, was killed by a 4-metre long shark while swimming off the popular Auckland beach of Muriwai yesterday afternoon.

Nigel Bradbury from the nearby town of Kumeu was at the beach with his daughter when he filmed the dramatic moment on his phone.

Dad dragged out to sea in shark feeding frenzy

''I was going to have a swim but we decided to have a picnic instead, and then we saw the inflatable (rescue boat) racing along the beach along with the quad bike towards Maori Bay,'' he told The New Zealand Herald.

Mr Bradbury said a police car parked next to him and within three minutes the police officer was in the rescue boat shooting at the shark to release Mr Strange's body.

''You could see it clearly, even though it was a fair way offshore. The water spraying up when he fired the gun - rapid fire and then you could hear the sound,'' he said.

Mr Bradbury said the officer shot at the shark in three rapid bursts.

''I've never heard anything like that before," he said.

It took about 30 minutes to recover the body, with witnesses claiming the shark refused to let go until police shot at it.

Police said it was possible up to three sharks had been feeding on fish and birds in the water and Mr Strange swam straight into their path.

Muriwai Volunteer Lifeguard Service chairman Tim Jago said Mr Strange was "a good water man" and was well known to the lifeguards who tried to save him.

He told media the lifeguards had been traumatised, and were being offered support and counselling.

He said the shark that attacked the man was believed to be a 4m great white.

Mr Strange was a TV commercial director and had worked around the world on several projects.

His first short film, Aphrodite's Farm, won the prestigious Crystal Bear award for Best Short Film at the Berlin Film Festival.

In a statement released last night Strange's family said they are "grieving the loss of a glorious and great father, husband and friend", TVNZ reported.

''We are in deep shock,'' they said.

Muriwai Beach and others nearby will remain closed until Saturday following the attack and lifeguards will continue to search the ocean for any sign of sharks.

Shark deaths are uncommon in NZ, with only 14 known fatal shark attacks since records began about 1837.

The last death was in 2009, when a kayaker was mauled by a great white, but it is not known whether he drowned before the shark found him.

Before that the last death was in 1976.