A human rights group says it has evidence that South Sudan government- forces deliberately suffocated more than 60 men and boys in a shipping container.
Amnesty International said They then dumped the bodies in a field in Leer Town, Unity State,.
Researchers said they had found the remains of skeletons from the killings, which are said to have taken place last October.
Thousands of people have been killed and millions displaced since 2013.
Lama Fakih from Amnesty in a statement said "Dozens of people suffered a slow and agonising death at the hands of government forces that should have been protecting them. These unlawful killings must be investigated,"