Just when you thought it was safe to go back into the water, a ferocious, carnivorous South American piranha has been fished out of London's River Thames, environmental officials said Thursday. The 4-inch-long red-bellied piranha was dropped by a passing seagull onto the deck of a boat built to oxygenate the river. The Thames was declared "dead" in the 1960s but is now home to 119 types of fish. "It was very fresh and had obviously only just died. You could see the marks made by the seagull's beak on its back," fisheries officer Tom Cousins said. Experts were quick...