The World Food Program (WFP) is shutting down its operations and terminating contracts with employees in the northern, rebel-held portion of Yemen , following restrictions and other harassment from the Houthi rebels, UN officials said on Thursday.  This is likely to exacerbate already dire humanitarian conditions in the impoverished Arab country amid a long-running civil war that first flared up in 2014.  According to UN officials with direct knowledge of the plans, the WFP's 365 remaining