A senior South Sudanese diplomat has been detained without charge by the National Security Service (NSS) for more than a month, her family has revealed.

Ambassador Regina Akur Nyok, Deputy Head of Mission to China, is being held at the NSS headquarters in Juba, commonly known as the “Blue House.”

Before her diplomatic posting, Nyok served as deputy office manager and key administrative aide to President Salva Kiir after her appointment in November 2025.

She had previously worked as chief cashier in the Office of the President.

A relative, Majokrial Mathiang, said on Monday that the family remains in the dark about the reasons for her arrest.

He said some relatives have tried to visit her but were denied access by security personnel.

“We don’t know the reasons why she was arrested,” Mathiang said.

“She was working as deputy ambassador to China; she is an active diplomat.”

Mathiang expressed concern that a high-ranking official could be imprisoned without apparent involvement from the Ministry of Foreign Affairs.

He called for her immediate release or for the government to present her before a court of law, noting that her prolonged detention without charge violates domestic legal standards.

Under South Sudan’s National Security Act, the agency has broad powers to arrest and detain individuals without a warrant, though the law requires detainees to be brought before a judge within 24 hours — a requirement that is rarely followed.

The South Sudan Diplomatic and Consular Service Act of 2011 states that the Ministry of Foreign Affairs is responsible for managing the administrative consequences of a diplomat’s arrest, including immediate suspension pending investigation.

The Ministry of Foreign Affairs and the Office of the President have not publicly confirmed whether they were notified of the arrest.

Authorities have issued no statement on Nyok’s detention.

The case comes amid a broader crackdown on high-profile figures in the finance and security sectors, with several officials targeted over corruption allegations since the beginning of the year.