Saudi Arabia’s aviation regulator has extended the closure of the kingdom’s main airport following two deadly strikes over the weekend, as Yemen’s Houthi rebels continued launching missiles at the country.

The kingdom’s General Authority of Civil Aviation (GACA) announced on Monday that the suspension of operations at King Khalid International Airport in Riyadh had been extended. Several airlines, including Flydubai, Emirates, Etihad Airways, Qatar Airways, and Air India, have canceled flights to and from Riyadh.

Houthi strikes on the airport on Saturday left 12 people dead, including four Saudi nationals, and more than 300 injured. Another attack the following day killed a Pakistani national and injured 11 others.

The Houthis, an Iranian-backed Shiite group, have described the strikes as “deterrence operations,” accusing Saudi Arabia of maintaining an illegal “siege” of the parts of Yemen under their control.

Early on Tuesday, General Turki Al-Malki, spokesman for the Saudi-led coalition, said coalition forces had intercepted two Houthi ballistic missiles launched toward Khamis Mushait, a city in southwestern Saudi Arabia.

Videos posted on social media reportedly show Saudi air defenses launching interceptors into the sky.