The United Nations has suspended all travel into areas held by Yemen’s Houthi rebels after seven more of their staff were detained by the group.
The Houthis have previously detained UN staffers, as well as individuals associated with the then US Embassy in Sanaa and aid groups.
“Yesterday, the de facto authorities in Sanaa detained additional UN personnel working in areas under their control,” a UN statement read.
“To ensure the security and safety of all its staff, the United Nations has suspended all official movements into and within areas under the de facto authorities’ control.”
Before Friday, the UN had a total of 16 Yemeni staff in Houthi detention.
Staffers found seven others had been taken and halted their work, which provides food, medicine and other aid to the impoverished nation.
In June, the UN acknowledges 11 Yemeni employees had been detained by the Houthis under unclear circumstances as the rebels increasingly cracked down on areas under their control.
Several dozen others from aid agencies and other organisations are also in detention.
The UN added that it was “actively engaging with senior representatives” of the Houthis, who have held Yemen’s capital since 2014.
The Iranian-backed rebels have been at war with a Saudi-led coalition battling on behalf of the country’s exiled government since 2015.
UN Secretary-General António Guterres said that “their continued arbitrary detention is unacceptable.”
“The continued targeting of UN personnel and its partners negatively impacts our ability to assist millions of people in need in Yemen,” he warned in a statement.
The Houthis did not acknowledge the UN’s decision, which came as they have otherwise been trying to de-escalate their attacks on shipping and Israel after a ceasefire was reached in Gaza.
US President Donald Trump separately has moved to reinstate a terrorism designation he made on the group late in his first term that had been revoked by President Joe Biden, potentially setting the stage for new tensions with the rebels.
The Houthis earlier this week said they would limit their attacks on ships in the Red Sea corridor and released the 25-member crew of the Galaxy Leader, a ship they seized in November 2023.
However, the Houthis have run a campaign targeting those with Western ties for some time.
The group has been airing repeated programmes on television channels they control parading people they describe as working with Western intelligence agencies or the Israelis.
The war in Yemen has killed more than 150,000 people, including fighters and civilians and created one of the world’s worst humanitarian disasters, killing tens of thousands more.
The Houthis’ attacks on shipping during the Israel-Hamas war have helped deflect attention from their problems at home.
But they have faced casualties and damage from US-led air strikes targeting the group for months.