SANAA (AFP) - Yemeni Shia rebels handed over to mediators on Monday the first of five Saudi soldiers held captive since their three-month border war with the kingdom, a rebel spokesman said. The Saudi soldier, Yahya Abdullah al-Khuzai, was han-ded over today (Monday) in the city of Saada to mediators, working on implementing a four-day-old truce between the Yemeni government and the rebels, Mohammed Abdul Salam told AFP by telephone. Meanwhile, thirteen Yemeni soldiers died when a military helicopter evacuating wounded servicemen amid a fledgling ceasefire with Shiite rebels crashed in the northern mountains, the defence ministry said on Monday. Sundays accident in the Kahlan district, east of the provincial capital Saada, was the result of a technical fault, the official Saba news agency quoted a ministry spokesman as saying. The helicopters four-man crew and the seven wounded soldiers they were evacuating all died, as did two soldiers in a military vehicle which the aircraft crashed into, the spokesman said. A third soldier on the ground was wounded. The accident came on the third day of a truce between the government and the rebels aimed at bringing an end to six years of conflict in which 250,000 people have fled their homes.