Candles are put in a heart-shaped layout to mourn the victims at Maelbeek metro station Brussels, Belgium, March 25, 2016. Two suicide blasts hit the departures hall of Brussels International Airport and a subway carriage at the Maelbeek station, close to the European Union institutions on Tuesday, killing at least 31 people and injuring over 300 others.(Xinhua/Gong Bing)
