Australia's most famous beach reopened Friday, hours after a surfer's arm was shredded by a shark — the second shark attack in Sydney in as many days.The 33-year-old man, whose name was not released, was bitten Thursday around dusk at Sydney's popular Bondi Beach and suffered severe arm injuries, police said. Other surfers helped him to shore, where volunteers helped to stop his bleeding.The man underwent a 10-hour surgery at St. Vincent's Hospital, and was in serious but stable condition Friday, hospital spokesman David Faktor said."We could see all of his bones cut like with a big knife. It was very clear," French tourist Mikael Thomas, 21, told Australia's Fairfax Media.Lifeguards sounded the beach's shark alarm and cleared the water. Surfer James McIntosh, 29, said he tied a leg rope around the victim's arm as a tourniquet."I just kept pulling that leg rope as hard as I could. As soon as we put the tourniquet on there wasn't any bleeding," he told Fairfax.On Wednesday, a Navy diver lost his hand after fighting off a shark in Sydney Harbour, not far from the Opera House. His leg was also badly mauled.A recent string of shark attacks across Australia has left some swimmers jittery. In December, 51-year-old Brian Guest vanished while snorkeling with his son off a beach in Western Australia. A piece of his wet suit was later found, and officials said he was almost certainly eaten by a shark.Last month, a 13-year-old surfer in the island state of Tasmania was dragged under water by a 16-foot (5-meter) great white shark, and a 31-year-old surfer was bitten while surfing at a remote beach in New South Wales state the same day. Both survived.The following day, a shark latched onto the leg of a snorkeler in southern New South Wales. The man survived after pummeling the creature with his fists until the shark let go.Most experts agree the cluster of attacks is a freak coincidence and say there is no evidence of an increase in the country's shark population. Nevertheless, some have argued that cleaner, nutrient-rich waters have boosted the animals' reproduction and drawn them into shallow waters.Although sharks are often spotted off Australia's beaches, fatal attacks are rare. On average, just one person is killed by a shark in Australia each year, according to the Australian Shark Attack File database.