The Iran-allied Houthis, who are battling the internationally recognised government of Yemen's President Abd Rabbu Mansour al-Hadi, often fire missiles or mortars into southern Saudi regions including Jizan and Najran, and often test Saudi defences with guerrilla-style incursions.
Saudi Arabia and its Gulf Arab allies intervened in Yemen's war in March 2015 to support Hadi's government. Several dozen Saudi soldiers have been killed in clashes along the country's long, rugged border with Yemen.
Image grab from a video posted in social media that shows an explosion in Jizan area.
A Saudi soldier was killed on Friday when Yemen's Houthi group attacked across the border into the kingdom's southern Jizan province, state television al-Ekhbariya reported.
