Airmen from the United Arab Emirates stand by a Chinook helicopter in a military base in the frontline conflict zone of Marib in central Yemen September 17, 2015. Armed with high-tech Western weaponry, Gulf Arab soldiers are fighting with newfound determination against what they see as the expanding influence of Iran, their non-Arab and Shi'ite Muslim arch-foe, in a war that has ravaged Yemen for six months. The oil-producing province of Marib has become a key battlefield between Iranian-allied Houthi militia and a coalition of Yemenis and Emirati, Saudi and Bahraini troops. Marib forms a gateway to the Yemeni capital Sanaa 120 km (75 miles) to the west, which the Houthis seized last year. REUTERS/Noah Browning