Four Saudi citizens and three foreign residents of the kingdom have been killed in a cross-border rocket attack by Yemen's Houthi rebels, the official Saudi Press Agency reports.
The attack hit the city of Najran, near the Yemeni border in the south-west of the kingdom, the agency reports, quoting the region's civil defence chief Ali al-Shahrani.
The attack came after the Arab coalition launched an investigation Tuesday following international condemnation of an air raid on Monday that Doctors Without Borders (MSF) said killed 11 people at a hospital it supports.
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Twelve people were killed Tuesday in an airstrike by a Saudi-led coalition on the house of a Yemeni tribal sheikh, a health ministry official in the rebel-held capital Sana'a said.
The International medical charity Doctors without Borders (MSF) said eleven people were killed and 19 were injured when a hospital it supports in northern Yemen was hit by airstrikes on Monday.