A missile strike attributed to Yemen's Iran-backed Houthi rebels killed 12 people and wounded 309 others at Riyadh's King Khalid International Airport on Saturday.

Saudi civil aviation authorities confirmed the toll early Sunday and said some of the injured were in critical condition. The victims included four Saudi citizens, two Bangladeshis, and one each from the United States, Jordan, Palestine, Syria, Sudan, and Egypt. The attack struck a passenger terminal, sending travelers fleeing and forcing the suspension of operations at the facility that serves Saudi Arabia's capital.

The Saudi-led coalition backing Yemen's government condemned the strike as a war crime and vowed a firm response. Coalition spokesman Maj. Gen. Turki al-Maliki described it as a terrorist act targeting civilians. This marks the deadliest such incident in the kingdom in more than a decade and follows earlier Houthi attacks this week on Riyadh and other Saudi airports that killed at least three more people.

Houthi officials claimed responsibility and said the strikes aimed to shut down the airport. The group has intensified its campaign against Saudi targets amid an escalation in the Yemen conflict, where Saudi-backed forces are fighting to reverse Houthi territorial gains and threats to shipping lanes.

The attack exposed gaps in Saudi air defenses during a period when the kingdom seeks to position Riyadh as a global hub. All flights were diverted, and foreign embassies advised citizens to avoid the area. US officials, including Secretary of State Marco Rubio, condemned the strikes, which killed an American citizen.

Fighting between the Houthis and Saudi-supported Yemeni forces has intensified in recent weeks, with both sides accusing the other of hitting civilian sites. The Houthis control large parts of Yemen and receive support from Iran, a factor that has prolonged the regional conflict.

Saudi authorities are assessing damage while hospitals treat the wounded. The coalition has warned of further military action against Houthi positions in response to the latest assault on civilian infrastructure.