Armed conflict in South Sudan continued Sunday as opposing factions vie for control of the region. The country's government announced that it was no longer in control of Bentiu, the capital of Unity State, which is a major oil-producing section of the young country.

According to Reuters, at the head of one side is South Sudan's president, Salva Kiir, and leading the other is former Vice President Riek Machar, who was dismissed in July. The two have long been political rivals. Kiir is from the Dinka ethnic group, while Machar is a Nuer, and the conflict has raised fears of an ethnic civil war.

United Nations compounds have also reportedly been looted, and the U.S. carried out an airlift evacuation for more than a dozen Americans at the UN's Bor compound over the weekend. One day prior, Special Operations had tried to attempt an evacuation, but the aircrafts came under fire and were forced to turn back. Four servicemen were wounded in the incident.

President Obama said he monitoring the situation in a letter to the Speaker of the House and Senate President, writing, "As I monitor the situation in South Sudan, I may take further action to support the security of U.S. citizens, personnel, and property, including our Embassy, in South Sudan."