United Nations human rights chief Volker Türk has demanded an urgent investigation into the death of Mohammad el Shami, a UN Human Rights Office employee who had been held by Yemen’s Houthis since June 6, 2024.

In a statement issued Saturday and reported by Euronews, Türk’s office described Shami’s detention as arbitrary. His family said he had died more than a month earlier, but that they had only recently been notified.

Türk said the family had received no explanation of the cause or circumstances of Shami’s death. He called on Houthi authorities to disclose relevant medical and detention records, preserve evidence and allow independent scrutiny of any stated cause of death. He also demanded accountability for wrongdoing.

Calling the death a “heartbreaking loss” for the UN, Türk expressed condolences to Shami’s family and concern for other detained UN employees, including seven members of his own office. He renewed his appeal for the immediate and unconditional release of detained UN personnel, humanitarian workers and civil society workers.

Yemeni Prime Minister Shaya al-Zindani condemned Shami’s death and said the Houthis bore full responsibility. He said more than 70 UN staff members and dozens of humanitarian workers remained in Houthi custody.