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The State Department said it is actively warning Americans about Houthi forces, after U.S. embassies across the Middle East issued new security alerts, CBS News reported on October 20.

Deputy assistant secretary Edgar Vasquez said: "We are actively warning U.S. citizens about the very real threat the Houthis pose and urging them to heed official guidance." The alerts say hostilities could spread rapidly and without warning beyond areas already affected. They urge Americans to prepare for flight cancellations and airspace closures.

The warnings follow a Houthi strike on Riyadh's King Khalid International Airport earlier this month. Saudi authorities put the toll at no fewer than 13 dead and more than 300 injured, including one American citizen. We reported the attack when the count stood at 12.

Fighting continued this week. On October 20, the Saudi-led coalition said it intercepted a Houthi ballistic missile aimed at Riyadh and a drone near the capital. A strike on a Yemeni government military camp on October 19 killed 73 recruits and wounded more than 200. A Houthi attack in Taiz killed two teenage girls.

A U.S. Mission alert dated October 17 said Riyadh's airport operations were suspended. Jeddah and Dammam were operating with some delays and cancellations. Airports in Bahrain, Jordan, Oman, Qatar and the UAE remained operational.

The same alert said U.S. citizens have been detained for photographing government buildings, airports and impact sites. U.S. government employees need Chief of Mission authorization to use any Saudi airport and may not travel within 20 miles of the Yemen border.

CBS reported that restrictions on U.S. diplomatic operations in parts of the region have been in place since the United States and Israel went to war with Iran in February. Officials describe them as temporary.

President Trump has declined repeated requests from Crown Prince Mohammed bin Salman for direct U.S. military intervention, though he has not ruled out joining airstrikes. Secretary of State Marco Rubio, speaking in India, called interceptors probably the most in-demand product in the defense field.

The latest guidance follows the US Embassy Beirut alert we covered on October 19, which warned that Iran and aligned groups may target US interests worldwide.

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