Intense clashes erupted Thursday in southern Yemen between forces loyal to the beleaguered president and the Shiite rebels whose assaults have pushed the Arabian Peninsula country into chaos.

Airstrikes targeted the palace of Abed Rabbo Mansour Hadi in the southern port city of Aden, to which he fled last month after escaping captivity by the rebels, known as Houthis. The rebels now control the capital, Sanaa.

The air raids followed a siege earlier in the day at the airport in Aden, where Hadi has set up a rival governing authority. The split raises the specter of an all-out civil war and could drag Yemen into a proxy conflict between the region’s two most powerful countries: Sunni Saudi Arabia and Shiite Iran. Hadi’s authority in the south is backed by Riyadh, while the Houthis, who are followers of the Zaydi sect of Shiite Islam, have received increasing support from Tehran. […]