The search for an international student who went missing off Fairy Meadow Beach resumed at 8am on Tuesday.
The 28-year-old man, who is a University of Wollongong student, was swimming with at least three friends around 6.40pm on Sunday, October 30, when he got stuck in a rip.
"A witness saw him raising his arm when he was in difficulty," Surf Life Saving Illawarra duty officer Anthony Turner said.
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A land and air search was initiated and then called off an hour later due to fading light.
The search resumed at 7.30am on Monday, with crews scouring the water and coastline from Towradgi to Port Kembla.
Marine Rescue NSW Inspector Stuart Massey said the conditions were "very challenging for crews".
"Conditions are extremely choppy with large swell, making it difficult to see," he said.
Wollongong Police District Acting Inspector Tanya Smith said the man was wearing black swimmers and goggles at the time he entered the water.
"We are still looking for him alive, but as the time goes on it does become more difficult for us to have a positive outlook. However there are a number of resources out there giving it our very best opportunity to find this man," she said.
The man and his friends were swimming around 100 metres north of Fairy Meadow Surf Club when he disappeared.
"It was quite a powerful, strong rip. It was moving for quite a considerable amount of time," Mr Turner said of the conditions at the time the man went under.
"It would have been difficult and quite frightening to get out if you were in that rip."
As the sun rose at Fairy Meadow Beach on Monday morning, the missing man's friends were there waiting and hoping.
The man and woman had binoculars and a drone and were combing the area looking for their friend.
"It's so beautiful but so deadly," the man's friend said.
A UOW spokesman said the university was saddened to learn one of its students was missing.
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"The university is providing support and counselling to staff and students affected by this incident," he said.
Multiple dye packs, which release a bright green substance, were dropped into the water during the search to help rescuers determine which way the currents and undertows were moving.
While Fairy Meadow Beach is patrolled seven days, the time the man went swimming was outside patrol hours.
The beach remains closed as the search and rescue operation continues.
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