In May 2019, Yemen’s Houthi rebels sent an explosive drone to Najran airport, which is used by thousands of civilians daily. Najran, 840km southwest of Riyadh, lies on the Saudi-Yemen border and has repeatedly been attacked by the Houthis.

They targeted a Patriot missile air defense system and weapons depot ate the same airport. The unmanned aircraft was intercepted and destroyed by the Saudi air force. Attacks on Saudi Arabia had largely subsided since last year amid United Nation-led peace efforts.

The conflict that began in late 2014 has killed tens of thousands of people, many of them civilians. About 24.1 million – more than two-thirds of the population – are in need of aid. The United Nations has described the war in Yemen as the world’s worst humanitarian disaster with millions facing famine and with disease rampant.