Six humanitarian aid workers were killed in South Sudan on Saturday when they were caught in an ambush while traveling from Juba to Pibor.

The United Nations Office for the Coordination of Humanitarian Affairs (OCHA) said in a statement that the deaths of the aid workers represent the highest number of humanitarians killed in a single incident since the conflict began. The UN statement did not identify the agencies or identities of those involved.

“I am appalled and outraged by the heinous murder yesterday of six courageous humanitarians in South Sudan,” said Eugene Owusu, the humanitarian coordinator for South Sudan. “At a time when humanitarian needs have reached unprecedented levels, it is entirely unacceptable that those who are trying to help are being attacked and killed.”

Saturday’s attack was the third serious incident this month in which aid workers were targeted. Two people died in a March 14 attack in Yirol East as a convoy was responding to a cholera outbreak. On March 10, the local staff of an international NGO were held for four days before being released.

“Every time an attack of this nature happens, we say that it must never happen again. And yet it does,” Owusu said.  “I implore all those in positions of power to step up to their responsibilities and stop this, as they are ultimately accountable for what happens under their watch.”

The intentional attacks may be war crimes under international law, the statement said.

At least 79 aid workers have been killed in South Sudan since the beginning of the December 2013 crisis, including at least 12 killed in 2017.

Image: UNMISS file photo