A man has been taken to Shellharbour Hospital with leg injuries after a suspected shark attack in Lake Illawarra.
The 23-year-old was was snorkelling near the Windang Boat Ramp at 10.45am today when he was bitten on the leg.
The man flagged down boat users who helped him to shore before calling emergency services.
Bendigo Bank Australian Aerial Patrol was on the scene within 10 minutes but failed to spot any sharks in the water. However, general manager Harry Mitchell believes a shark attack was likely.
``I would not be surprised if it was a bull shark,'' he said.
``They are a nasty little shark, very aggressive.''
The attack follows two other incidents over the weekend.
Jonathon Beard, 31, of Brisbane, was surfing with friends at Fingal Beach in northern NSW about 9.30am yesterday when he was bitten on his upper left thigh.
And 13-year-old Hannah Mighall was saved from a 5m white pointer off north east Tasmania when her cousin hit the shark and took her to shore on his surfboard.
Craig Roberts, manager of life saving at Surf Life Saving NSW, said bull sharks, great white sharks and tiger sharks were the three species associated with attacks on humans.
"Hammerheads and grey nurses are the most sighted but bull, tiger and great white sharks are the ones that attack," Mr Roberts said.
FULL REPORTS IN TUESDAY'S MERCURY