Saudi army artillery fire shells towards Yemen from a post close to the Saudi-Yemeni border, in southwestern Saudi Arabia, on April 13, 2015 . Saudi Arabia is leading a coalition of several Arab countries which since March 26 has carried out air strikes against the Shiite Huthis rebels, who overran the capital Sanaa in September and have expanded to other parts of Yemen. AFP PHOTO / FAYEZ NURELDINE        (Photo credit should read FAYEZ NURELDINE/AFP/Getty Images)