A British expatriate living in South Africa is said to be fighting for his life after he was attacked by a shark whilst swimming in South Africa Wednesday.

The 42-year-old unmarried accountant, who was not identified, was swimming at Fish Hoek Beach, which had been closed after a sighting of a shark in the waters, the BBC reported. The white warning flag was flying. It is believed that the man dived in at the closed beach, where he was a regular swimmer, despite repeated warnings. A lifeguard rushed over to warn him to get out, but was too late.

The man was stabilised at the scene and airlifted to Constantiaberg Medi-Clinic in a critical condition.

"The man was conscious when paramedics attended to him on the beach, but was sedated on-scene by paramedics in their efforts to stabilise the patient," National Sea Rescue Institute spokesman Craig Lambinon told the South African Press Association.

A shark spotter stationed on the beach was warned by a fellow spotter on the mountain that someone had entered the water. The spotter then ran to Clovelly Corner to try to get the swimmer out of the water, but he was too late.

"It appears [the victim] was rescued from the water by a bystander who left the scene before we could identify him," Lambinon said.

The Sun reports that the shark could be seen in the bay after the mauling and all local beaches remained closed.