CAIRO (AP) — Houthi rebels in Yemen removed U.N. equipment and assets and took them to an undisclosed location without explanation, the world body said Friday, the latest in a series of restrictions by the Iran-backed group. Julien Harneis, the United Nations' resident and humanitarian coordinator for Yemen, said the Houthis entered at least six unstaffed U.N. offices in Sanaa on Thursday and removed most of the telecommunications equipment and several U.N. vehicles without U.N. authorization. The move will likely further hinder urgently needed humanitarian assistance in Houthi-controlled areas and marks the latest escalation in the Houthis’ crackdown on U.N. staff and aid groups.