The civil war in South Sudan is heating up again, and Americans are at risk.

A mission to rescue some American citizens ended when the evacuation helicopter took fire from rebel soldiers. Four US service members were injured and the mission was aborted.

CNN:

Four U.S. service members were injured when gunfire hit their aircraft during an attempt to evacuate Americans from a violence-hit South Sudanese city Saturday, a Pentagon spokesman said.

The troops were trying to land in Bor when gunfire from the ground hit the aircraft, Pentagon spokesman Rear Adm. John Kirby said.

"The aircraft diverted to an airfield outside the country and aborted the mission. The injured troops are being treated for their wounds," Kirby said.

The aircraft went to Nairobi, Kenya, so the wounded could be treated, a senior U.S. official said.

The evacuation attempt came after days of deadly clashes in South Sudan, including a reported coup attempt in the capital, Juba, last weekend. Bor also has been the site of heavy fighting, the U.S. official said.

The violence prompted the United States and other nations to take steps to protect their citizens. U.S. President Barack Obama had sent 45 service members to South Sudan to support U.S. personnel and the American Embassy; the government of neighboring Kenya said it would send troops to help evacuate 1,600 Kenyan citizens.

This latest round of violence is because the president made the mistake of dismissing cabinet members from an opposing tribe. The governnment says hundreds of soldiers and civilians have been killed.

Meanwhile, we've got people on the ground caught in the midst of another civil war. With rebels taking potshots at our aircraft, you would hope the next attempt will include a little more firepower to protect them.