People attend a mourning ceremony for Polish President Lech Kaczynski and people on board the crashed Tu-154 aircraft, in Warsaw, capital of Poland, April 11, 2010. On Saturday morning, a Polish government plane carrying a delegation for the 70th anniversary of the Katyn crime crashed at Smolensk, 18 kilometers from Katyn where WWII Polish officers were murdered 70 years ago. All 96 passengers aboard the plane were killed including President Lech Kaczynski and his wife Maria.[Ma Shijun/Xinhua]