Militia commander Germain Katanga is to face trial in Kinshasa over new charges in his native country. The warlord was scheduled to leave prison in January after serving the term handed down by the ICC in The Hague.
Katanga was scheduled to appear before court on Wednesday over killing UN peacekeepers in 2005, in the aftermath of the bloody conflicts in DR Congo.
The International Criminal Court had already sentenced the militant leader for war crimes, including murder and pillage, mostly connected to a 2003 raid which killed some 200 people.
The international judges determined that Katanga supplied weapons to his FPRI militia.
However, the court "did not have enough evidence to show that Katanga was present and in full control of the rebels at the time of the Bogoro massacre," Geraldine Mattioli-Zeltner from Human Rights Watch told DW.
During the years of conflict, the warlord became known as Simba, or Lion in Swahili.
Katanga was arrested in 2005 and delivered to the Hague some two years later. However, the ICC only sentenced him in early 2014, deciding on a 12-year prison term.
The court subsequently cut his sentence for good behavior and voicing regret, and sent Katanga to Kinshasa ahead of his planned release.
The 37-year old was scheduled to leave prison on January 18, after spending over ten years behind bars.
Crackdown on war criminals
On the day of his release, the DR Congo authorities refused to set Katanga free.
"He will not leave" prison, Justice Minister Alexis Thambwe Mwamba told the AFP news agency, adding that the militia leader was implicated in cases "just as serious," as the one before the ICC.
Mwamba specifically mentioned Katanga's alleged role in the death of nine UN peacewkeepers in the gold-rich Ituri region.
Many crimes from the two civil wars that shook Congo between 1996 and 2003 remain unpunished. In recent years, however, Congolese authorities have taken steps against war crime suspects. Several senior army officers have been convicted by the domestic courts, in addition to high-profile cases in The Hague.
dj/kms (AFP, Reuters)