Ison suffered serious leg and arm injuries during the attack off the north coast of New South Wales which reportedly occurred early on Friday.
Ison managed to scramble back to shore where an onlooker applied a tourniquet to his leg, according to the police statement.
The Australian is reportedly in hospital in a serious but stable condition.
Mick Fanning's 'shark attack' actually nothing of the sort
A friend of the 52-year-old who observed the incident, Geoff Hill, told local media the attack was “like watching a Mick Fanning replay”.
Hill told the Northern Star newspaper: "We were just paddling out this morning and Craig was 20m ahead of me."
"But it grabbed him as he turned around," he said, saying Ison was pulled under the water.
"I paddled to him but by then he was on his board and paddling back.
"It was like watching a Mick Fanning replay."
Fanning escaped unharmed after he punched a shark during a competition in South Africa in an incident which went viral around the world.
The former world champion managed to board a jet-ski after the attack which occurred during the World Surf League event in Jeffreys Bay, which was broadcast live.
Mick Fanning shark
Image credit: Eurosport
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