The South Sudan government has lost control of two key cities in the world's newest nation, as violence that has claimed hundreds of lives and sent thousands fleeing their homes entered a second week Monday.
Army spokesman Philip Aguer told VOA News that soldiers loyal to former vice president Riek Machar were in control of Bor, the capital of Jonglei state, and Bentiu in oil-rich Unity state, but insisted that the military is "capable of dealing with the rebellion" and will re-establish "full control of the national army over South Sudan."
Many in South Sudan and the international community fear that the violence which began eight days ago in Juba, in what South Sudanese President Salva Kiir has said was an attempt led by Machar to oust him, is both stoking and being fueled by tribal tensions between the minority Nuer -- Machar's ethnic group -- and Kiir's majority Dinka group.
The commander of the Fourth Army Division in Bentiu, James Koang Chuol, who last week insisted that the unrest would not take hold in Unity state, took control of the city at the weekend and declared himself governor after what he said was an attempt, ordered by Juba, to assassinate him.
"The leadership of South Sudan ordered the commanding officer of the tanks unit to kill me," and other division leaders, all of whom are members of the Nuer community, Koang said, adding that his troops thwarted the assassination bid and killed all 15 members of the tanks unit.
Aguer denied that the army had tried to kill Koang or anyone else.
Koang has imposed a curfew in Bentiu, and promised tough action against anyone caught looting. He also issued an order on state radio, calling for Governor Joseph Nguen Monytuel, who was appointed by Kiir in July, to turn himself in.
Neither Nguen nor Deputy Governor Mabek Lang De Mading have responded to text messages and phone calls from VOA News. They and other state leaders are thought to be in hiding.
U.S. Secretary of State John Kerry discussed with Kiir in a phone call over the weekend "the need to prevent ethnic violence" and expressed concern for the "welfare of thousands of internally displaced persons fleeing the conflict, as well as for the safety of U.S. citizens in South Sudan."
A report released last week by Human Rights Watch said that many victims of the violence were targeted because of their ethnicity. At least 500 people were killed in Juba when clashes erupted there on December 16, and scores more have been killed as fighting spread around the country.
The U.N. humanitarian office said the violence has displaced 62,000 people across half of South Sudan's 10 states, and that more than 40,000 have taken refuge on U.N. bases and in U.N. compounds.
U.S. 'Could Take Further Action' in South Sudan
The United States has deployed nearly 100 troops to South Sudan to reinforce security at the U.S. embassy in Juba and to help evacuate Americans, and President Barack Obama said Sunday he "may take further action" to protect Americans in South Sudan.
Four U.S. military members were wounded when their military aircraft was fired on over South Sudan at the weekend during a mission to evacuate Americans from Bor.
The U.S. State Department said U.S. citizens and nationals of "partner countries" were evacuated from Bor on Sunday.
U.N. Secretary-General Ban Ki-moon called on South Sudanese leaders to find a "political means" to address the conflict. The violence poses a "dangerous threat" to the future of the young country, Ban said.
The U.N. Mission in South Sudan (UNMISS) relocated non-critical staff from Juba to the Ugandan city of Entebbe on Sunday, a day after evacuating civilian staff from its compound in Bor.
At the same time, UNMISS said it will reinforce its military presence in Bor and Pariang, in Unity state, to allow it to continue to fulfill "its mandate to help protect South Sudanese civilians."
The head of UNMISS, Hilde Johnson, stressed that the mission was "not abandoning South Sudan."
"We are here to stay, and will carry on in our collective resolve to work with and for the people of South Sudan," Johnson said.
Two U.N. peacekeepers were killed in Jonglei state last week after a large group of armed youths, suspected of belonging to the Nuer ethnic group, surrounded a U.N. operating base in Akobo at which dozens of ethnic Dinka had sought refuge, and opened fire.
Students Urge Dialogue
In Wau, the capital of Western Bahr el Ghazal state, third-year education student Benychieng Gheny Khor told VOA News he sought refuge with the United Nations mission last week after relations between Nuer and Dinka students "went very poor" when some students blamed deaths in the violence in Juba on members of his Nuer ethnic group.
But after Western Bahr el Ghazal Governor Rizik Zachariah Hassan told the students not to "create lines based on our tribes," and assured them that the state government would "provide you with security", Gheny said he was prepared to move back to his university housing.
Gheny urged the national government to learn from the example set by Western Bahr el Ghazal, where there have been no reports of fighting, and from the students at the university in Wau, where business major Akej Philip Dut -- a Dinka -- said at a meeting, "As Nuers and Dinkas and other tribes. I can assure people that we are living peacefully and never had any problems."
"A dialogue has to be made between the two parties. The leaders have to come down for dialogue and negotiation to the round table and discuss these matters between themselves," Gheny said.
"The victims at the moment are the civilians and citizens of South Sudan," he said.
Kiir has said he is willing to engage in dialogue to try to end the violence raking the country, and that he is open to negotiations without preconditions.
In an interview last week with Radio France Internationale, Machar said he was open to talks with foreign diplomats to try to end the fighting, but insisted that Kiir step down because "he has failed to maintain unity among the South Sudanese people, which was won after a long and painful battle."
South Sudan became the world's newest nation in July 2011, six years after the signing of a comprehensive peace agreement that ended decades of civil war in once-unified Sudan, in which some two million people died.