Saudi Arabia blamed Iran for an attempted missile attack on Riyadh’s international airport, saying it could be considered an “act of war” and that the kingdom had the right to defend itself.

Iranian-backed Houthi fighters in Yemen fired a missile at the airport in Riyadh on Saturday. It was intercepted by Saudi air defenses, though the explosion shook homes and could be heard in the capital of about 6.5 million people.

The missile attack has sharply escalated tensions between Saudi Arabia and Iran, rivals for regional hegemony that have been fighting a proxy war in Syrian and Yemen since 2015. It also comes as Saudi Crown Prince Mohammed bin Salman takes a stronger stance against Iran, accusing the Islamic Republic of seeking to control the Muslim world.

“Iran’s role and its direct command of its Houthi proxy in this matter constitutes a clear act of aggression that targets neighboring countries, and threatens peace and security in the region and globally,” the Saudi-led military coalition fighting the Houthis said in a statement on Monday. The attack could be considered “an act of war against the kingdom of Saudi Arabia,” it said. (…)