Saudi border guards 'on alert' near Houthi-controlled Yemen

The guards on the Saudi Arabian side of the border with Yemen are "on alert" for attacks by the Houthi rebels in control of parts of the country.

The Saudis are supporting the Yemeni government in their conflict with the rebels, and have launched air strikes.

Kim Ghattas reports from the border, which has been largely inaccessible to the international media

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