The International Criminal Court is holding a multi-day hearing beginning Thursday to determine whether it should go forward with the trial of Lord's Resistance Army commander Dominic Ongwen.
He is facing 70 charges of war crimes and crimes against humanity, including murder, enslavement, pillaging and cruel treatment of civilians.
After hearing from prosecutors and the defense during the hearing that is expected to last no more than five days, a judge will decide if there is enough evidence to warrant a trial.
Ongwen turned himself in a year ago to U.S. special forces in the Central African Republic, ending a 10-year effort to have him face charges for LRA atrocities.
FILE - Joseph Kony, leader of the Lord's Resistance Army during a meeting with a delegation of 160 officials and lawmakers from northern Uganda and representatives of non-governmental organizations, July 31, 2006, Congo near the Sudan border.
The group is accused of killing and kidnapping tens of thousands of people across Uganda and three nearby countries during the past 30 years.
Human Rights Watch said Thursday's proceedings mark an "important step for accountability" for crimes committed in Uganda.
"The LRA is a notoriously brutal force that for decades has attacked civilians across a wide swath of East and Central Africa," said Elise Keppler, associate international justice director at HRW. "The ICC case against Dominic Ongwen is the first of its kind for LRA crimes and helps to show the ICC's unique role as the global court of last resort."
The ICC has charged four other top LRA members, but two of them have since died and the others, including commander Joseph Kony, remain at large.
Kony was also indicted by the court in 2005 and remains one of the world's most notorious fugitives from justice.