DOHA A Saudi border guard was killed by a landmine explosion on the border with Yemen, the Saudi state news agency SPA said on Friday, quoting an interior ministry spokesman.
Houthi forces in Yemen, battling its internationally recognised government, have fired hundreds of mortars into southern Saudi Arabia and tested Saudi defences with guerrilla-style incursions since Riyadh intervened in Yemen's civil war last year.
SPA said the mine exploded when it was struck by a vehicle transporting water along a border road on Thursday evening in Saudi Arabia's Jizan region.
U.N.-led negotiations have failed to bring peace to Yemen, the poorest Arab country. Saudi Arabia and its Gulf Arab allies intervened in the war after the Iran-allied Houthis overran the capital Sanaa in 2014, driving the government into exile.
At least 10,000 people have been killed.
The Saudis say their intervention, for which U.S. military personnel are providing logistical support, has halted Iranian expansionism in Yemen. Critics say the war has made Yemen more volatile and emboldened al Qaeda militants.
Saudi Arabia has reported dozens of its soldiers or civilians killed in the 20-month-old conflict.
(Reporting by Tom Finn; editing by Mark Heinrich)