The United Nations World Food Programme (WFP) announced today that three staff members who disappeared in South Sudan’s Upper Nile State earlier this month are still missing and that parts of the state remain too insecure to continue working as before.

“We are extremely worried about the fate of our missing colleagues and are working hard for their safe return,” said WFP Executive Director Ertharin Cousin. “Our staff take enormous risks every day to bring vital aid to people in critical need.”

The three WFP staff members disappeared on April 1 en route to a food distribution. They were traveling in a convoy from Malakal to Melut when inter-communal fighting erupted along the road on which they were traveling.

WFP lost contact with the three men and has not heard from them since, “despite intense efforts to reach them,” according to a press release from the UN agency.

The United Nations humanitarian leadership has recommended to halt services in the area where the staff disappeared. UN Humanitarian Coordinator Toby Lanzer disclosed in a message on the social networking site Twitter on 18 April, “3 WFP staff are missing in the area of Akoka & Fashoda; as such the Humanitarian Country Team recommended to suspend the aid operation there.”

Following this meeting, the WFP today announced, “Because of increasing concerns about staff safety, WFP is re-assessing its ability to work in some parts of Upper Nile State. The agency plans to temporarily reduce its operations in those areas where it no longer believes it’s safe to work.”

WFP Deputy Country Director Eddie Rowe in Juba said, “We regret that we must temporarily suspend food assistance in Akoka and Fashoda counties.

“The agency has been working with authorities in Juba, Malakal and Akoka to seek information about the whereabouts of the three missing staff members, to no avail.”

The United Nations says 10 humanitarian workers have been killed in Upper Nile State since the start of South Sudan’s conflict more than 16 months ago.

Another WFP staff, Mark Diang, was abducted at gunpoint in October 2014 from the airport in Malakal, capital of Upper Nile State and hasn’t been heard from since. “WFP holds grave concerns for his safety and continues to follow up with the government regarding his status.”