The country's membership in the African Union has been suspended, putting a freeze on the AU's military effort there to catch notorious warlord Joseph Kony.
M23's reported connections with Uganda and Rwanda complicate a resolution in eastern Congo.
Some 100 Special Forces soldiers are advising and training regional troops searching for Joseph Kony, leader of the Lord's Resistance Army, in central Africa.
After South Sudan seizes Heglig oil fields, which both countries claim, Sudanese President Omar al-Bashir declares war. How can international community prevent a regional conflict?
Joseph Kony showed his face to the world in 2006. Peace talks in the South Sudan city of Juba between 2006 and 2008 held out the promise of an end to Africa's longest insurgency. Here's how they ended.