SYDNEY—A swimmer on a Sydney beach in Australia died after being attacked Wednesday by what witnesses described as a 4 1/2-meter (15-foot) great white shark. “This person had suffered catastrophic injuries as a result of the attack and there was nothing paramedics could do when we arrived on scene,” New South Wales state Ambulance Inspector Lucky Phrachnanh said. It is the first fatal shark attack in Sydney since 1963. A witness, Kris Linto, said the swimmer was in the water when the shark “came and attacked him vertically.” “We heard a yell and then turned around, it looked like a car just landed in the water, big splash,” he told Nine News TV. Police closed Little Bay Beach as they continued to search the area for the shark. According to researchers with the International Shark Attack File, Australia last year led the world with three unprovoked shark-related deaths, followed by …