UN Secretary General Antonio Guterres has called for the immediate and unconditional release of 11 UN staff arrested by Houthi authorities in Yemen.
The workers were detained by security forces in raids on the World Food Programme (WFP), children's charity Unicef and the World Health Organization (WHO), news agencies and the UN said.
Sunday's raids took place in the capital, Sanaa, and port city of Hudaydah, UN Special Envoy for Yemen Hans Grundberg said.
Grundberg noted that the Houthis had already been holding 23 other UN workers arrested since 2021.
Houthi authorities have not commented on Sunday's arrests.
In a statement, Guterres expressed strong condemnation of the arbitrary detentions of UN personnel by the Houthis, including forced entries into UN premises and the seizure of property.
While the reasons for targeting UN workers remain unclear, these staff have been essential in providing support to ordinary Yemenis amid a dire humanitarian crisis.
One worker who was previously arrested died in detention earlier this year, revealing the severe risks involved.
In addition, the Houthis have detained around 20 Yemeni employees of the US embassy for three years.
Grundberg emphasized that the ongoing detentions severely hinder aid delivery and peace advancements in Yemen.
Earlier this year, the UN suspended movements in Houthi-held areas after several personnel were detained, showcasing the escalating risk for humanitarian operations.
The recent arrests come amid heightened tensions following an Israeli attack that killed Houthi officials, marking an intensified conflict as the Houthis continue to retaliate against perceived threats.
Since the Houthis ousted the internationally recognized government in 2015 during a civil war, their control has resulted in a staggering humanitarian crisis, with over 150,000 casualties, 4.8 million displaced, and 19.5 million people requiring assistance.
