UPDATE 11.20am: EXPERTS from the Department of Primary Industries have told police from Richmond Local Area Command that the shark responsible was a Great White, between 3m and 4m long.
Sweeps of the beach have failed to find any sign of the shark; patrols continued throughout the week, with local beaches closed to the public as a precaution.
The NSW Police Force's helicopter, PolAir, conducted sweeps of the coastline again today, without any sightings.
Police said beaches between Ballina and Lennox Head remain closed today to the public; however, this is due to advice from the surf lifesavers who had concerns about rough surf, rather than the shark.
Advice from the Department of Primary Industry expert to NSW Police is that the shark responsible is unlikely to have remained in the immediate area, and once surf conditions have eased, the beaches will be open.
A post mortem examination is being conducted on Mr Nakahara today.
Police are liaising with Mr Nakahara's family in Japan.
INITIAL REPORT: A GREAT White shark at least three metres long was responsible for Monday's fatal attack on Tadashi Nakahara, the Department of Primary Industries has confirmed.
The identification was made by a Fisheries NSW shark expert who conducted a forensic analysis of the victim to estimate the size of the shark's jaw and gaps between its teeth.
The expert also studied footage from the Coastalwatch surf website livestream camera trained on Shelly beach, which documented the attack.
The footage will not be released to the public, but is understood to have revealed the shark attacked from the side of the surfer, not from underneath as previously reported.
Beaches across Ballina Shire remain closed today.
A police helicopter has continued a search for the Great White from the air this morning from 8.30am this morning, although to date no shark has been seen since the attack.
Richmond police Inspector Doug Connors said police were conducting a joint meeting with Surf Life Saving Far North Coast and the shark expert from Fisheries NSW to assess when it might be safe to reopen the beaches.
Inspector Connors said the main issue was "the likelihood of the shark still being in the area".
"Our primary focus is on public safety," he said.
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