A man is believed to have died after being bitten by a shark while surfing off the coast of South Australia. It is the state's second fatal attack in six months. Witnesses reported seeing the 55-year-old man surfing at Granites Beach south of Streaky Bay on the Eyre Peninsula when he was attacked by a shark about 10.20am on Tuesday. The incident follows a fatal attack on another surfer at Walkers Rock Beach in May, just 100km down the coast. The body of 46-year-old teacher Simon Baccanello has never been recovered. Earlier this month, 64-year-old Pamela Cook suffered serious leg injuries when she was bitten by a shark at Beachport on the state's southeast coast. The man's body is yet to be found and police have pledged to continue their search. Australian Associated Press