Demonstrators attend a torch-bearing march marking the centenary of the mass killing of Armenians by Ottoman Turks in Yerevan, Armenia April 24, 2015. Armenia marked the centenary on Friday of a mass killing of Armenians by Ottoman Turks with a simple flower-laying ceremony attended by foreign leaders as Germany became the latest country to respond to its calls for recognition that it was genocide. Turkey denies the killing of up to 1.5 million Armenians in what is now Turkey in 1915, at the height of World War One, constitutes genocide and relations with Armenia are still blighted by the dispute. REUTERS/David Mdzinarishvili TPX IMAGES OF THE DAY