A man aged 40s has died in New Zealand after a shark attacked him while swimming off Muriwai Beach, about 40 kilometres west of Auckland. However, police said they open fired at the shark from a boat and witness accounts said they were actually two sharks hovering at the time. Investigations are now being made if the man was indeed killed by which shark or by the bullets that flew from the cops' guns.

The unidentified man was bitten and downed by a large shark, whose specie was likewise unknown.

Pio Mose, a fisherman, told Fairfax Media the man went out swimming alone, about 200 metres offshore, when he was attacked.

"All of a sudden ... we saw the shark fin and next minute, boom, attack him then blood everywhere on the water," he said.

Instinctively, Mr Mose called 111, while his friend ran to get help.

"He was still alive, he put his head up, we called him to swim over the rock to where we were."

"He raised his hand up, and then while he was raising his hand up we saw another attack pull him in the water."

Responding police authorities, who joined surf life guards, shot at the shark, estimated to be about four to five metres long, from a boat in order to veer the victim from its fangs. About 20 shots were fired.

Although it rolled away, police cannot exactly say it they were able to kill it or not since there was also a second shark in the water at the time.

According to Te Ara: the Encyclopedia of New Zealand, there have been at least 44 recorded unprovoked shark attacks in New Zealand since 1852.

Still, Clinton Duffy, a shark expert with the Department of Conservation, maintained shark attacks in New Zealand, compared to Australia, "are much lower levels."

"It's possibly a function of how many people are in the water in New Zealand's cooler climate," he said in the Washington Post.

Although sharks do often come to shore to feed and to give birth during the Southern Hemisphere summer, he maintained these still rarely translated to attacks and death.

"Ninety-nine percent of the time they ignore people," he said. "Sometimes, people get bitten."