UN images reveal 18,000 destroyed structures in South Sudan region
United Nations satellite images show at least 18,000 structures have been destroyed in the Yei area of South Sudan.
The images obtained by the Associated Press are one of the most significant caches of evidence of widespread destruction in the country's civil war.
The Yei region has become an epicentre of fighting between government and rebels after a peace deal collapsed in July.
The UN has highlighted the area for its risk of genocide, and an AP reporter late last year during a visit to Yei saw charred bodies with their arms bound.
The UN satellite images show how population centres like Yei, Morobo and Bazi have been mostly devastated. In parts of the towns of Kaya and Morobo nearly every building is in ruins.
The images do not show who is responsible for the destruction, but monitors of South Sudan's peace deal said last week that in most instances in Yei "buildings were deliberately set on fire by government forces".
A spokesman for President Salva Kiir called the satellite images "exceedingly rubbish".
"Where are the people? That means that 18,000 families are dead or are displaced," Ateny Wek Ateny said.
Government officials have blamed rebels and wildfires for the destruction in Yei, the peace deal monitors said, adding that investigators found that unlikely.
Satellite imagery is increasingly being relied on by investigators to document destruction during South Sudan's three-year civil war, which has killed tens of thousands and seen more than 1.7 million people fleeing the country.
About half of them have poured into neighbouring Uganda, creating the world's fastest-growing refugee crisis.
Investigators are turning to satellite images as fighting continues to make on-the-ground work dangerous and as South Sudan's government is accused of restricting access to places like Yei.
The peace deal monitors have said government forces denied UN officials and investigators access to one Yei village.
A separate collection of UN satellite images obtained by the AP show that destruction of property in the southern Yei region began as early as October, and that a build-up of military forces began as early as September.
Other satellite images from Amnesty International show the aftermath of fighting that erupted in the capital, Juba, in July and left hundreds dead.
In one image, the rights group points out a "probable mass grave" visible at a military barracks, likely for troops killed in battle.
By itself, satellite imagery provides incomplete evidence for human rights investigations because it can be misleading or does not provide enough detail, said Josh Lyons, a satellite imagery analyst with Human Rights Watch.
"It's only by piecing together both the testimony and imagery that we come to a higher level of understanding of not only what happened but who ultimately is responsible," Mr Lyons said.
The United States and others have been urging accountability.
Last month, the UN commission of inquiry for South Sudan was given broader powers to pursue human rights abuses like mass rape and torture, with the new ability to collect and preserve evidence and point the finger at suspected perpetrators.