According to a statement from the U.N.'s International Office of Migration spokeswoman, the two soldiers were killed while escorting a convoy traveling west from Seiyun to Marib. No IOM staff, who were on an unspecified humanitarian mission, were injured in the attack, it said. No further details about the Friday incident were given.

A tribal leader from the area and a U.N. official told The Associated Press that the ambush took place near the town of Al-Abr, in Yemen's eastern Hadramout province. Both spoke on condition of anonymity out of fear of reprisals.

In a separate statement issued on Friday by Lt. Gen. Saleh Mohammed Timis of Yemen's Special Tasks Battalion _ an official branch of the Saudi-backed army _ the two men were identified as Salem Saeed Qarwan and Salem Mubarak Al-Bahri.

The attackers have not been identified.

Yemen's ruinous conflict began in 2014 when Iranian-backed Houthi rebels came down from the northern mountains and seized the capital of Sanaa. In response, a Saudi Arabia-led coalition intervened in 2015 to try to reinstate the internationally recognized government to power. The conflict has since turned into a proxy war between regional foes Saudi Arabia and Iran, killing some 150,000 people and resulting in one of the world's worst humanitarian crises.

Eastern and southern Yemen, which fall under Arab coalition control, have seen an uptick in infighting between different armed groups in recent months. The fatal clashes have often pitted Southern forces, who currently control most of southern Yemen, and those loyal to the internationally recognized government. In August, a day of clashes between rival factions of the Arab coalition killed 35 troops in the southern province of Shabwa.

Al-Qaida also has an enduring presence in eastern and southern Yemen. In February, suspected militants of its global network kidnapped five U.N. workers in southern Abyan province.