The UN has called for the immediate release of 11 of its members detained by the Houthi movement in Yemen.
The employees were taken to various parts of the conflict-torn country in what appears to be a coordinated crackdown.
U.N. spokesman Stéphane Dujarric said the world body was using all available channels to secure their safe and unconditional release as quickly as possible.
The armed group considers itself part of an Iranian-led “axis of resistance” against Israel, the United States and the West as a whole, and has declared its support for the Palestinians in the Gaza Strip.
The Houthis target commercial shipping in the Red Sea, triggering retaliatory airstrikes from the United States and its allies.
Several employees of other international organizations were also arrested, according to reports citing officials of Yemen’s internationally recognized government.
Phones and computers were seized in the raids on workers’ homes and offices, which come after months of Houthi attacks on commercial ships in the Red Sea.
The Mayyun Organization for Human Rights said Houthi intelligence agents simultaneously targeted 18 aid workers from several groups in Amran, Hudaydah, Saada and Sanaa.
Officials told the Reuters news agency that several members of the US-backed National Democratic Institute (NDI) had been targeted.
These detentions demonstrate the risks facing aid workers in a country where a decade-long civil war is believed to have killed more than 150,000 people and sparked one of the world’s worst humanitarian crises.
They come as the Houthis face growing economic woes and airstrikes by a U.S.-led coalition.
The armed group controls Yemen’s capital – Sanaa – and the northwest of the country, running a de facto government that collects taxes and prints money.
Yemen’s internationally recognized government is based in the southern port of Aden.
