The United Nations World Food Program said on Tuesday that one of its staff members had died in detention in northern Yemen, where the UN has repeatedly called for the Houthis to free detained UN employees.

WFP did not specify when or how its employee, who it said had been detained on January 23 with six others, had died.

The United Nations paused all operations in Yemen’s Sa’ada region on Monday after more UN staff were detained by the Houthi authorities, deputy UN spokesperson Farhan Haq said.

“Heartbroken and outraged by the tragic loss of WFP team member, Ahmed, who lost his life while arbitrarily detained in Yemen. A devoted humanitarian and father of 2, he played a crucial role in our mission to deliver lifesaving food assistance,” WFP Chief Cindy McCain said in a post on X.

The Iran-aligned Houthis have controlled most populated parts of Yemen, including the capital Sanaa, since seizing power in 2014 and early 2015. Since 2021 the Houthis have detained dozens of UN staff. The group now has some 24 UN staff in detention.

Yemen has been the focus of one of the world’s largest humanitarian operations during a decade of civil war that disrupted food supplies. WFP says it provided assistance to 15.3 million people, or 47 percent of the population, in 2023.