REPORTING FROM JOHANNESBURG, SOUTH AFRICA -- Shark spotters at Fish Hoek faced two mysteries Wednesday.
Why did a 42-year-old swimmer enter the water when a shark-warning flag was flying? And, after the swimmer was attacked by a great white shark, who was the stranger who rescued the man from the water, then disappeared?
Shortly after the attack, video of a large shark swimming slowly in shallow water off Clovelly Beach at Fish Hoek, about 20 miles south of Cape Town, was posted on YouTube. A photograph of the shark-warning flag at the beach was posted on Twitter by an editor of local news service News24.
The beach was closed after the shark was spotted and the shark-warning flag, showing a black shark on a white background, was raised.
"When the victim entered the water, the beach was still closed and the shark flag, indicating the presence of a white shark, was flying," Cape Town city authorities said in a statement.
The British expatriate, who reportedly has lived in the area for years, was swimming rapidly fairly far out to sea when the shark attacked, shark spotters said.
Shark spotters are stationed by municipal authorities at beaches to watch for sharks and warn swimmers. The city statement said the spotter on the beach tried to warn the man to leave the water, but the shark attacked before he could get the swimmer’s attention.
The shark severed the man’s right leg and part of his left leg, according to the National Sea Rescue Institute. The man was the only person in the water at the time.
Details about the mysterious man who rescued the man were sketchy. The National Sea Rescue Institute said someone dragged the injured man from the water.
"It appears he was rescued from the water by a bystander who left the scene before we could identify him," said a spokesman for the National Sea Rescue Institute spokesman, Craig Lambinon.
"On arrival, a 42-year-old man was found on the shore suffering complete amputation of his right leg, above the knee, and partial amputation of his left leg, below the knee,' Lambinon said.
The swimmer was taken by helicopter to a Cape Town hospital; he was listed in critical condition late Wednesday.
Video: Amateur video provided to News24 shows a great white shark basking offshore a beach south of Cape Town. Credit: News24