Tunisia's Oussama Mellouli celebrates after winning gold in the men's 10km marathon swimming at Hyde Park during the London Olympic Games Friday. — Reuters LONDON – Pool or lake, it makes no difference to Ous Mellouli. As long as there's water involved. The Tunisian won the grueling 10-kilometer race at the London Games Friday to become the first swimmer to win medals in both the pool and open water at the same Olympics. Mellouli, who won bronze in the 1,500-meter freestyle last week, pulled away from a small group of leaders in the fifth of six laps and clocked 1 hour, 49 minutes, 55.1 seconds in the murky waters of The Serpentine in Hyde Park. It was the second gold of Mellouli's Olympic career, having won the 1,500 at the 2008 Beijing Games. After pulling himself up on to the makeshift finishing dock, Mellouli flexed his muscles, beat his chest and let out a few screams — then yelled again after getting the gold medal hung around his neck — marking Tunisia's first victory of the games. Beijing bronze medalist Thomas Lurz of Germany took silver this time, 3.4 seconds behind, and first-time Olympian Richard Weinberger of Canada was third, 5.2 seconds back. The 25-man field completed six laps of a 1.66-kilometer course in near-perfect conditions as fans lined both banks of the rectangular lake under bright sunshine. The only previous swimmer to win medals in both the pool and open water at the Olympics was David Davies of Britain. He took bronze in the 1,500 free at the 2004 Athens Games and silver in the inaugural 10K Olympic race in Beijing four years ago. Mellouli, who trains at the University of Southern California, is relatively new to open water swimming, but he also won the Olympic qualifier in Setubal, Portugal, in June. Meanwhile, the crowd favorite was Benjamin Schulte, a 16-year-old from Guam, who finished far behind all of the other competitors. Fans stuck around and applauded loudly when Schulte finally finished nearly 14 minutes after Mellouli. — AP