The two-week hearing marks the first time evidence of war crimes in Sudan's Darfur region will be aired in court.

The procedure is not a trial, but aims to establish whether the case against Bahar Idriss Abu Garda is strong enough to merit a trial, court officials said Friday.

Abu Garda, 46, turned himself in to the court in May and declared his innocence to charges of murder, attacking peacekeepers and pillage stemming from the September 2007 rebel assault on the African Union camp in Haskanita, northern Darfur.

Prosecutor Luis Moreno Ocampo said the case is a landmark in protecting international peacekeepers during armed conflicts.

"Attacking peacekeepers is one of the most serious crimes in the world," he said. "Peacekeepers are there exposing their lives to protect civilians."

Two Nigerian soldiers who survived the attack will testify at the hearing along with a senior Nigerian commander, Moreno Ocampo said.

Abu Garda will return to the Netherlands to attend the hearing and again declare his innocence. His lawyer, Karim Khan, said Abu Garda had nothing to do with the attack.

He "did not direct it, did not order it, did not plan it, did not condone it," Khan said. "Rather, he condemned it."

Abu Garda was an early member of Islamist-leaning rebel organization the Justice and Equality Movement, but formed his own splinter group after falling out with the movement's leaders in 2007. Prosecutors say he now leads a group called the United Resistance Front.

The case against him is a milestone in faltering attempts by the world's first permanent war crimes tribunal to prosecute atrocities in Sudan's Darfur conflict, which began in February 2003 when ethnic African rebels took up arms against the Arab-dominated Sudanese government in Khartoum, claiming discrimination and neglect.

U.N. officials say the war has claimed at least 300,000 lives from violence, disease and displacement and forced some 2.7 million people from their homes.

Sudan's President Omar al-Bashir has been charged with crimes against humanity and war crimes for allegedly masterminding deadly attacks on African tribal settlements and refugee camps throughout Darfur.

But Al-Bashir refuses to recognize the court's authority and has vowed never to surrender. He has traveled to several countries with friendly links to his regime in open defiance of an international warrant for his arrest.

Moreno Ocampo also has charged a government minister and a leader of the government-allied janjaweed militia with war crimes in Darfur but they also remain out of his reach in Sudan. The court has no police force to arrest suspects.

"The case against Abu Garda is about justice for crimes against peacekeepers sent by African states to protect people in Darfur," said Richard Dicker, director of Human Rights Watch's International Justice Program.

It also demonstrates that international prosecutors want to protect Africans, as well as prosecute them. The court has been criticized by some observers because all four of the investigations it has launched are in African nations _ Sudan, Congo, Uganda and Central African Republic.

"The case highlights the ICC's concern for protecting African civilians and sends a clear message to warring parties that these attacks will not be tolerated," Dicker said.