A man looks at the offices of the education ministry's workers union, destroyed by Saudi-led air strikes, in Yemen's northwestern city of Amran August 19, 2015. A Saudi-led Arab coalition has been bombarding the Iranian-allied Houthi rebel movement - Yemen's dominant force - since late March in a bid to reinstate exiled President Abd-Rabbu Mansour Hadi, who has fled to Riyadh. REUTERS/Khaled Abdullah