(AP) — The Iran-backed Houthis on Sunday raided offices of the United Nations’ food and children’s agencies in Yemen’s capital, detaining at least one U.N. employee, officials said.

Abeer Etefa, a spokesperson for the World Food Program, told The Associated Press that security forces raided the agencies’ offices in Houthi-controlled Sanaa Sunday morning.

Also raided were the offices of the United Nations’ children agency, UNICEF, according to a U.N. official and a Houthi official, who spoke on condition of anonymity because they weren’t authorized to brief the media.

Ammar Ammar, a spokesperson for UNICEF, said there was “an ongoing situation” related to their offices in Sanaa, without providing further details.

The U.N. official said contacts with several other WFP and UNICEF staffers were lost and that they were likely also detained.