[Photo Credit: Reuters]

The third attack this week on Riyadh’s international airport on Saturday left at least 12 people dead and ​more than 300 wounded, Saudi authorities said, as Iran-backed Houthis escalated the campaign they launched this summer against the kingdom.

The dead included four Saudis, two ‌people from Bangladesh and one person each from the US, Jordan, Palestine, Syria, Sudan and Egypt, the Saudi civil aviation authority said. At the latest count, officials said, 309 were wounded.

Hospitals were flooded with wounded brought by ambulance and helicopter, people briefed on the matter said. Some were in critical condition.

Saturday’s attack, the deadliest in the kingdom in more than a decade, occurred without warning, with no alert issued by Saudi ​Arabia’s threat warning system. This week’s two previous attacks on King Khalid International Airport left four people dead and caused heavy damage to a Saudi commercial plane ​parked on the tarmac.

The deadly strikes exposed vulnerabilities in the kingdom’s defence capabilities as it wages an air campaign against the Houthis to ⁠support a ground war by the Yemeni government against the Iran-backed group.

A Saudi-led military coalition vowed to respond to the attack.

Saudi Arabia and the Yemeni government have claimed hundreds ​of strikes on targets in Houthi-held territory. The Houthis have said these killed civilians including women and children. Reuters could not independently verify those claims.

All flights were diverted from Riyadh on ​Saturday, and operations at the airport that serves a city of roughly 8 million people were temporarily suspended, the Saudi civil aviation authority said.

The head of the Houthi media office said in a post on X after the attack that the group had “shut down Riyadh international airport”. The Houthis have said airliners should avoid Saudi airspace, declaring it a zone of military operations after the Saudi-backed Yemeni government launched an ​offensive against the group on Monday.

US President Donald Trump, speaking to reporters outside the White House, was asked whether Washington planned to join Saudi strikes on the Houthis.