Saudi forces and Yemen's Houthi militia traded heavy artillery fire which blew up part of the main border crossing between the two countries overnight, residents said on Sunday, an escalation of the two-month war.
The Haradh border crossing, the largest for passengers and goods between the world's top oil exporter, Saudi Arabia, and its impoverished neighbor, was evacuated amid shelling which razed its departure lounge and passport section, witnesses said.
Residents of several Yemeni villages in the area left their homes and fled from the frontier, which has turned into a front line between the kingdom and the Iran-allied rebels.
Saudi Arabia has led an Arab coalition bombing the Houthis and backing southern Yemeni fighters opposing the group and loyal to the exiled government in Saudi Arabia headed by President Abd-Rabbu Mansour Hadi.
The Sunni Muslim states believe the Shi'ite Houthis are a proxy for influence by their arch rival Iran, but their campaign has yet to reverse the rebels' battlefield gains.
Residents in the central city of Taiz said Houthi forces and pro-Hadi fighters fired tank and artillery shells at each other throughout the city overnight, and the Houthis seized control of a military base on a strategic mountaintop.