Russia and Ukraine accused each other of shelling Europe's biggest nuclear power plant in southern Ukraine as the U.N. chief proposed a demilitarized zone at the site amid fears of a catastrophe. #Ukraine #Russia #Nuclear #News #Reuters Subscribe: http://smarturl.it/reuterssubscribe Reuters brings you the latest business, finance and breaking news video from around the globe. Our reputation for accuracy and impartiality is unparalleled. Get the latest news on: http://reuters.com/ Follow Reuters on Facebook: https://www.facebook.com/Reuters Follow Reuters on Twitter: https://twitter.com/Reuters Follow Reuters on Instagram: https://www.instagram.com/reuters/?hl=en