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Fresh attacks struck two Saudi airports on Sunday, October 11, according to a security alert from the U.S. Mission to Saudi Arabia. The alert describes additional attacks on King Khalid International Airport in Riyadh and a targeted attack on King Fahd International Airport in Dammam.

A projectile hit domestic passenger terminals 3 and 4 at King Khalid, and the airport was closed for the day, CBS News reported. Saudi authorities said Dammam's airport was also attacked. Injuries there were not known at the time of reporting. The two airports sit about 400 miles apart.

The strikes follow Saturday's attack on King Khalid, which Saudi officials said killed at least 12 people and wounded 309. We covered that attack in an earlier Circuit Wire report. CBS said FlightAware counted 324 cancellations that day. Three Saudi civilians, including a Saudia Airlines captain, died in attacks on the same airport on Thursday, October 8.

The Houthis claimed the earlier strikes. They have said Saudi airports and airspace are potential targets and have warned passengers not to travel. They said Mecca and Medina would not be targeted.

The U.S. alert says American government employees need special authorization to use the airports in Riyadh, Jeddah and Dammam. It urges extreme caution at all major airports in the kingdom and warns of possible flight cancellations and airspace closures. It names Saudi Arabia Railways, SAT Transportation and SAPTCO as rail and bus options, and lists private car travel as another. Regular and emergency consular services remain available. Saudi Arabia stays under a Level 3 "Reconsider Travel" advisory.

Airline disruption is broad. CBS reported that Lufthansa, Air India, PIA, flydubai, Etihad, Emirates and Air Arabia have suspended Riyadh flights. The European Union Aviation Safety Agency has advised against operating in parts of Saudi airspace.

Governments differ on how far to go. The United Kingdom advises against all but essential travel to the Riyadh region, Najran, Jizan, Aseer and Taif. Germany, Australia and Canada advise against all travel to Saudi Arabia. The U.S. has no broad warning against travel to the country.

Fighting in Yemen continues. The Saudi-led coalition said it destroyed 136 military targets, CBS reported, and the Houthis say they still hold Mayun Island and the western coast. Talks between Washington and Tehran remain stalled.

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