south sudan
An SPLA soldier gestures as he sits in a vehicle in Juba, Dec. 21, 2013. Reuters

Three U.S. aircraft came under fire from unidentified forces Saturday while trying to evacuate Americans from the conflict in South Sudan, Reuters reports. The U.S. military said four of its members were wounded in the attacks. The U.S. aircraft came under fire while approaching the evacuation site, the military's Africa Command said in a statement. "The aircraft diverted to an airfield outside the country and aborted the mission." All three of the Osprey CV-22 aircraft involved in the mission were damaged.

President Obama warned that any move to take power by military means would lead to an end of U.S. and international community support for South Sudan.

Nearly a week of fighting in South Sudan threatens to drag the new country into an ethnic conflict two years after it gained independence from Sudan, with strong support from the United States.