U.N. officials say the World Food Program is shutting down its operations in northern, rebel-held part of Yemen. They said on Thursday that the WFP's 365 staff members in this part of Yemen will lose their jobs by the end of March. They blame the shutdown on crippling restrictions imposed by the Houthi rebels and harassment from Iranian-backed group. The development is likely to worsen the dire humanitarian conditions in Yemen. The Houthis have cracked down on U.N. workers and aid groups in their areas. Yemen has been one of the world's worst humanitarian disasters since the civil war began there in 2014.