He was well-liked in the local community. A local businessman told the Evening Standard: "He was a great guy, very popular with everyone."
Mr Nakahara was reportedly a passionate surfer who took to the water regularly. His Facebook page features dozens of photos of the beach and surfing.
Friends of Mr Nakahara told local cafe owner, Karen, the shark came out from nowhere.
"It just came up between a bunch of surfers," she told AAP yesterday.
"They weren't even that far out. He lost both his legs."
The victim's friends were shaken up and looked "white as a ghost" as they carried their mate's board away from the beach, the local said.
Ballina mayor David Wright said rescuers believed it was a great white shark.
'It must have been a huge, huge shark'
"For a shark to take the board and the person sitting on it, it's got to be very big," he said.
Local surfer Allan Baldock told the Guardian Australia that Mr Nakahara had been sitting on his board about 10m offshore.
"It went whack and he was thrown into the air ... it must have been a huge, huge shark," he said.
Police described Mr Nakahara's injuries as "substantial".
"He had leg injuries and they were substantial, they were injuries that led to a significant loss of blood," Mr Lindsay said.
Mr Nakahara had been surfing with up to four others. Two more surfers paddled out to help him.
"Unfortunately they could not stop the bleeding and at this stage we believe he died of blood loss," Mr Lindsay told ABC.
A shark expert would arrive in Ballina today to help identify exactly what type of shark attacked Mr Nakahara.
Searchers look for killer
Mr Lindsay said searchers were scouring a large area for the killer, believed to be "very large shark".
"The expert will assist us to determine what type of shark it was," he told ABC.
"Once we know what type of shark it is and receive advice on whether or not that shark poses a threat to humans, then we'll assess what we'll do about the shark."
Beaches in the area were closed after the fatality.
It came just one day after Jabez Reitman, 35, was attacked while sitting on his surf board off Seven Mile Beach near Byron Bay, only 30km north of Ballina.
He suffered a cut to his back and puncture wounds to his buttocks.
"Something just jumped out of the water and just grabbed me at my hip and dragged me off my board and took me under the water," he told ABC.
He came back up and paddled the 60m back to shore.
Third fatality in recent months
Yesterday's attack was the third shark fatality in 10 months in New South Wales.
In September, 50-year-old Paul Wilcox was killed by a great white shark while swimming at Byron Bay.
Christine Armstrong, 63, was killed by a shark at Tathra Beach in April last year while swimming in the morning.
Sharks are a regular feature in Australian waters and swimmers and surfers have had their share of encounters with the animals this summer.
Fatalities, however, are rare, although two teenagers died in shark attacks in December, one on the country's west coast and one on the east.
Experts say attacks by sharks are increasing as water sports become more popular.
- AFP, AAP, nzherald.co.nz
