Rwanda-backed M23 insurgents shot dead three boys who had picked up guns left by Congolese soldiers fleeing the rebel advance in eastern Congo, the U.N. said on Tuesday, adding the incident to a list of grave human rights violations reported during the conflict.

RWANDA: backed rebels have tightened their grip on Bukavu, a day after seizing the second major city in eastern Congo whose residents appeared resigned to their fate under the new rulers. On Sunday, M23 rebels captured the city of 1.