Shabwah campaign (March–August 2015)  The Shabwah campaign (March–August 2015) was a campaign for control of the Shabwah Governorate of Yemen, between the Houthis and Yemen Army units loyal to Ali Abdullah Saleh on one side, and militiamen and Yemen Army units loyal to Abdrabbuh Mansur Hadi on the other side. The offensive was also launched during a previously started AQAP offensive. On 29 March 2015, fighting centered in the oil-rich Usaylan region. 38 were killed in fighting between the Houthis and Sunni tribesmen. Tribal sources confirmed the death toll, and claimed only eight of them were from their side, with the other 30 either Houthis or their allies from the Yemeni military. The tribesmen were also reinforced by weapons received via 200 vehicles from tribes in the nearby province of Abyan. After the fighting, Houthi positions were hit by Coalition air-strikes. On 1 April, fighting at a major army base left 35 Houthi and allied army fighters, along with 20 tribesmen, dead. On 6 April, the Houthis were reported to be negotiating with local tribes for safe transit to Ataq, the provincial capital. However, additional fighting on the same day killed two Houthi fighters, while another eight were killed in an airstrike. Two days later, 10 Houthis, three Houthi-allied soldiers and three tribesmen were killed in further clashes. On 9 April, air-strikes hit the Houthi-held Muhra base, outside Ataq, after which the Houthis and their allies seized government and police installations in the city. Soon, hundreds of armed tribesmen mobilised on the outskirts of Ataq to attack the Houthis. Still, the Houthi capture of the provincial capital was reportedly facilitated by local tribal chiefs and security officials. On 10 April, 25 Houthi fighters were killed in a suicide car-bomb attack, carried out by Al-Qaeda in the Arabian Peninsula (AQAP), on their security post in the Bayhan region. As is the case in the neighboring Abyan Governorate, it was reported that AQAP fighters were ordered to fight alongside pro-Hadi forces against the Houthis. On 13 April, pro-Hadi tribal militia took control of two military bases belonging to units that were guarding oil facilities in the Belhaf area. 15 soldiers stationed at one base were killed. On 19 April, seven Houthis were killed in clashes in the province.