King Philippe - Filip of Belgium and Queen Mathilde of Belgium arrive to attend a homage ceremony on Place de la Nation in Brussels on March 24, 2016, two days after a triple bomb attack, which responsibility was claimed by the Islamic State group, hit Brussels' airport and the Maelbeek - Maalbeek subway station, killing 31 people and wounding 270 others. Belgian authorities are seeking a second suspect over the attack on a metro train in Brussels in which one suicide bomber has already been confirmed dead, police sources told AFP on March 24.  AFP PHOTO / KENZO TRIBOUILLARD / AFP / KENZO TRIBOUILLARD        (Photo credit should read KENZO TRIBOUILLARD/AFP/Getty Images)