A multi-agency search for a fisherman missing off Australia's east coast has been massively expanded.
The search, broadened on Monday afternoon, began after a 56-year-old man failed to return from a day of fishing.
He departed from Batemans Bay Marina on the NSW South Coast about 6am on Saturday.
Contact was made with the man about 10am but emergency services were called when he failed to return that night.
The search initially focused on an area between Ulladulla and Merimbula but was widened as it continued on Monday.
Led by the Marine Area Command, vessels, fixed-wing aircraft and helicopters have now scoured as far north as Port Stephens and as far south as the Victorian border - an area spanning about 700km.
Four Marine Rescue NSW vessels are involved.
The expanded search followed unconfirmed sightings of the man's eight-metre Arvor cruiser by members of the public.
Marine Rescue NSW Inspector Stuart Massey said crews were determined to find the 56-year-old.
"All of our dedicated volunteers are tired but ready to continue," he said.
"They are an incredible group of committed people."
There were almost 30 volunteers on the water on Sunday across six vessels, covering an area from Ulladulla to Merimbula and up to 22km seaward under the direction of police, Mr Massey said.
Surf Life Saving Australia and the Australian Maritime Safety Authority are also involved in the search.
