In 2001, Thomas Lubanga Dyilo founded the Union des Patriotes Congolais (UPC) and was commander in chief of its armed wing, the FPLC (Forces Patriotiques pour la Liberation du Congo).
Active in North Kivu, the group was involved in human rights violations including ethnic killings, torture, sexual violence and mutilations - all qualifying as crimes against humanity and war crimes. It is alleged that 3,000 child soldiers were recruited into the ranks of the FPLC. The group is now estimated to number a few hundred fighters.
On 17 March 2006, Lubanga was the first person arrested under a warrant issued by the ICC. His trial began in 2009 and was sentenced to 14 years in prison in 2012 for war crimes including recruiting child soldiers and forcing them to fight in a war.
Check out our Flipboard magazine - Who's who in the battle for DRC by IBTimes UK
In this series on the Democratic Republic of the Congo, IBTimes UK takes a closer look at the eastern regions of South and North Kivu where civilians are still at the mercy of armed groups and the Congolese armed forces, who have all been accused of committing serious war crimes.