The United Nations says its staff have found a mass grave in South Sudan's oil rich Unity State.
The United Nations says its staff have found a mass grave in South Sudan's oil rich rebel-held Unity State.
The organisation's human rights office says staff who visited the site on Monday in the northern town of Bentiu counted 14 bodies in the grave, and 20 more at a nearby river.
A spokeswoman for the Geneva-based UN office told The Associated Press on Tuesday that the bodies are among 75 ethnic Dinka who were reported to the UN as "unaccounted for and feared dead."
The dead reportedly belonged to the Sudan People’s Liberation Army.
There are also unconfirmed reports of at least two more mass graves in Jebel-Kujur and Newside, near the capital Juba.
Some 20,000 people seeking safety have crowded round the UN base in the capital.
The Government’s Minister of Information Michael Makuei Lueth claims the town of Bentiu is under the control of rebels loyal to the country's former Vice President, Riek Machar. He indicated the rebels were responsible for the killings.
South Sudan’s President Salva Kiir is Dinka, while Mr Machar is of Nuer ethnicity.
US Secretary of State John Kerry spoke Mr Machar on Tuesday when told Mr Kerry he is ready for talks with Mr Kiir, which are likely to take place in Ethiopia.
"I will form a high-level delegation, to which I will give full power to negotiate an accord," Machar told Radio France Internationale.
"We want Salva Kiir to quit power. We want a democratic nation and free and fair elections," he added.
Violence began spreading across South Sudan after a fight among Kiir's presidential guards in mid-December, which pitted Nuer against Dinka.
The UN Security Council is expected to vote Tuesday on a resolution to increase the number of UN troops in South Sudan from 7,000 to 12,500 following a call by Secretary-General Ban Ki-moon.
South Sudan’s top UN humanitarian official Toby Lanzer said on Monday that he believes the death toll from the 10 days of violence has surpassed 1,000, but added that there are no firm counts.
He estimated that there are more than 100,000 internal refugees across the country seeking shelter from the violence.