A rocket fired by Yemen’s Houthi rebels fell in the arrivals hall of the Abha international airport in Saudi Arabia on Wednesday, June 12, injuring more than two dozen people, according to the Arab coalition fighting the rebels.

Coalition spokesperson Colonel Turki Al Malki said in a statement carried by the official Saudi Press Agency that the incident was a “terrorist attack” that could amount to a “war crime” if the Houthis deliberately targeted civilians.

The military is working to determine the type of projectile used, he added.

Eight people were hospitalized for minor injuries after the missile hit the arrivals hall around 2 a.m. and the other 18 were given first aid treatment and released, Al Malki said. The injured included women and children, including a woman from Yemen and one from India.

The Houthis have claimed the attack, saying earlier that they targeted the airport in Asir province with a cruise missile, Saudi news website Al Arabiya reported.

The rebels have recently increased attacks on neighboring Saudi Arabia, and the kingdom regularly says it intercepts missiles and drones fired from Yemen.

Last month the Houthis claimed drone strikes that temporarily shut down a key oil piplijne in Saudi Arabia.

Al Malki said Wednesday that the coalition would “take urgent and timely measures” to deter the Houthis.

Saudi Arabia and its Gulf allies intervened in Yemen in 2015 after President Abd Rabbo Mansour Hadi fled the country as the Houthis swept through the country. Coalition airstrikes in Yemen have been blamed for the deaths of thousands of civilians.

The capital Sana’a remains in rebel hands.

The United Nations calls the war in Yemen the world’s worst humanitarian crisis, with around 10,000 people dead and millions at risk of starvation.