Two leaders of the Democratic Forces for the Liberation of Rwanda (FDLR) militia appeared in a German court yesterday.
They are charged with 26 counts of crimes against humanity and 39 of war crimes.
FDLR president Ignace Murwanashyaka and Straton Musoni, his deputy, have been in pre-trial detention since their arrest in 2009.
They are accused of masterminding atrocities in the eastern Democratic Republic of Congo (DRC).
Their trial comes after Germany, in June 2002, introduced a new International Penal Code to deal with the crime of Genocide and other crimes against humanity and terrorism.
Under this law, German prosecutors can try a civilian for crimes committed outside Germany.
The duo was arrested following a warrant issued by German Federal Prosecutors.
In 2009, German prosecutors highlighted 'systematic crimes' perpetuated by the FDLR against the civilian population where they killed thousands of Congolese, raped and recruited child soldiers.
The prosecutors say that as leaders of FDLR, they are, responsible for the crimes committed by the group.
In 2005, Murwanashyaka was blacklisted by the UN for violating an arms embargo aimed at promoting peace in the DRC, and subjected to a travel ban and freezing of his assets.