Rwandan President Paul Kagame has told CNN he doesn’t know if his country’s troops are in the east of the Democratic Republic of Congo (DRC), where fighting between the M23 armed group and Congolese soldiers has killed more than 700 people and injured thousands in recent days.

Fighting across the largest city in eastern Democratic Republic of Congo and "is still very much ongoing ... it's not over yet," senior U.N. official in Congo, Bruno Lemarquis, said on Monday after Rwandan-backed M23 rebels claimed to have control of Goma.

To better understand the three-year insurgency, have a look at some of our strongest reporting.