Yemen’s Houthis on Thursday claimed a new ballistic-missile strike on King Khalid International Airport in Riyadh, a day after a deadly hit on the same airport killed a Sudanese resident and wounded eight others.

Saudi authorities closed the airport after explosions were heard, with fire crews deployed and smoke visible. The Saudi-led coalition said it intercepted two ballistic missiles aimed at Riyadh and a third toward Khamis Mushait; debris damaged a kindergarten and a medical complex but caused no casualties, officials said.

Wednesday’s strike was the deadliest yet on the Saudi capital’s airport. On Tuesday, Houthi missiles hit Abha International Airport in the southwest, killing two female residents — one Moroccan and one Algerian — and wounding 28 others. The Houthis claimed responsibility for both attacks.

Lufthansa suspended flights to Riyadh through October 16, and Air India cancelled flights until October 10. The Houthis have warned international airlines against using Saudi airspace and urged people to stay away from oil facilities, which they called targets.

The escalation comes as Saudi-backed Yemeni forces press an offensive against the Houthis, who recently seized the Bab al-Mandeb Strait. Syria is considering deploying troops to help Saudi Arabia, Reuters reported.