A Spanish flag flies half-mast at Colon Square, in central Madrid, July 25, 2013. A train derailed outside the ancient northwestern Spanish city of Santiago de Compostela on Wednesday evening, killing at least 77 people and injuring up to 131 in one of Europe’s worst rail disasters. Spanish Prime Minister Mariano Rajoy declared on Thursday three days of official national mourning for the victims of the disaster. REUTERS/Susana Vera (SPAIN - Tags: DISASTER TRANSPORT TPX IMAGES OF THE DAY)

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