A train transporting skiers to a Austrian alpine resort caught on fire inside a mountain tunnel Saturday, trapping as many as 140 people, the mayor of a nearby town said. The train was reported to be around 600 yards inside the mountain. ''Some people have been rescued but we have no way of knowing if there is any more survivors,'' said Norbert Karlsboeck, mayor of Kaprun, a town some 50 miles south of Salzburg in the central Austrian Alps. A massive rescue operation was launched after the fire broke out at 9:30 a.m., with some 13 helicopters, teams of police, doctors and Red Cross workers all at the site, the mayor said. ''We do not know anything about the reason for the fire, only that it broke out on the train,'' Karlsboeck said. Police were calling on motorists to keep away from the area so as not to hinder rescue attempts, AP reports.