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The evening sky in Schwangau, southern Germany, is illuminated by lightning during thunderstorms
A streak of lightning is seen above the skyline of Nanning during a thunderstorm in Guangxi Zhuang, China
Lightning from a thunderstorm strikes on Thursday amid the wreckage of twisted cars and structures at Plaza Elementary School, where seven children were killed when a tornado hit Moore, Oklahoma. The tornado tore through the town on Monday, flattening neighbourhoods and destroying the elementary school with a direct blow as children and teachers huddled against winds of up to 200 mph.