Aug. 31 (UPI) -- At least 11 United Nations employees in Yemen were abducted by Houthi-controlled authorities Sunday after they raided World Food Program facilities in the capital Sanaa.

U.N. Secretary-General Antonio Guterres announced and condemned the abduction in a statement that also demanded the "immediate and unconditional release" of those detained.

The U.N.'s WFP provides life-saving food assistance to children and mothers in a country considered one of the world's worst humanitarian crises due to the nearly 12-year civil war between the Houthi militants and the internationally recognized Yemeni government.

The raid followed Israeli airstrikes on Houthi-controlled Sanaa on Friday, which killed its prime minister, Ahmed al-Rawai, along with several other ministers.

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