THE heads of six United Nations agencies and three humanitarian organisations issued a joint appeal to Yemen’s Houthi-led government on Thursday for the release of 17 members of their staff.

The appeal was echoed by a statement from several dozen nations and the European Union ahead of a UN security council meeting on Yemen, where special envoy Hans Grundberg said the Yemenis were holding the detainees incommunicado.

Yemeni authorities said on Monday that they had arrested members of an “American-Israeli spy network,” days after detaining the UN and international aid organisations’ staff.