A military convoy drives through mountains of al-Mahfad area of the southern Yemeni province of Abyan May 6, 2014 in this photo provided by Yemen’s defence ministry. Western embassies in Yemen heightened security measures on Thursday after increasingly bold attacks on foreigners by al Qaeda, even as the militant Islamists lost ground to an army offensive in the south. Picture taken May 6, 2014. REUTERS/Yemen’s Defence Ministry/Handout via Reuters (YEMEN – Tags: POLITICS CIVIL UNREST MILITARY) ATTENTION EDITORS – THIS PICTURE WAS PROVIDED BY A THIRD PARTY. REUTERS IS UNABLE TO INDEPENDENTLY VERIFY THE AUTHENTICITY, CONTENT, LOCATION OR DATE OF THIS IMAGE. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. NO SALES. NO ARCHIVES. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS