Child soldier-turned-warlord Dominic Ongwen denied 70 charges of war crimes and crimes against humanity on Tuesday when he became the first member of Uganda's brutal Lord's Resistance Army ever to go on trial.

Ongwen, 41, is also the first former child soldier to be tried by the International Criminal Court in The Hague for his role in the notorious rebel group led by the elusive Joseph Kony.

"In the name of God, I deny all these charges in respect to the war in northern Uganda," Ongwen said when he was asked to plead after all 70 charges containing a litany of horrific crimes were read out to him.

"I am not the LRA. The LRA is Joseph Kony, who is the leader," he told the court.

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"It was the LRA who abducted people. It was the LRA who killed them," Ongwen said, adding that he was "one of the people who had crimes committed" against them.

A self-styled mystic and prophet, Kony launched a bloody rebellion against Kampala some three decades ago seeking to impose his own version of the Ten Commandments on northern Uganda.

Reporting from The Hague, Al Jazeera's Neave Barker said Ongwen's trial was a "huge test of what the ICC is really able to achieve.

"There is a tremendous amount of hope as to whether or not the ICC will be able to deliver," Barker added.

"Among the charges he faces are murder, rape, and enslavement, including the enslavement of more than 30,000 children as child troops to fight in the frontlines of the Lord's Resistance Army."

Sadistic rituals 

More than 4,000 victims are taking part in Ongwen's trial and scores of others are expected to watch the trial unfold at four viewing sites in northern Uganda.

About 150 people, mostly subsistence farmers, crammed themselves into a room at Lukodi Primary School in northern Uganda to watch the opening day of the trial.

Squeezed onto rows of dilapidated wooden benches, villagers sat patiently waiting for the live transmission from the court to begin.

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"We have been waiting almost 11 years for justice," said Vincent Oyet, secretary of the local victims' group.

Victims have recounted the LRA's sadistic initiation rites imposed on kidnapped youngsters, who were forced to bite and batter friends and family to death, or to drink their blood.

The son of Ugandan schoolteachers, Ongwen was abducted as a child while on his way to school and most likely endured such horrors himself.

But ICC prosecutors say when Ongwen became an adult he turned abuser, helping to orchestrate the abduction and enslavement "of children under the age of 15 to participate actively in hostilities".

Systematic killings

Prosecutors allege that from 2002 to 2005, Ongwen "bears significant responsibility" for attacks in northern Uganda, "systematically" ordering the killings of civilians sheltering in four camps including in Lukodi.

Victims died in an orgy of violence, while survivors had their lips and ears cut off. In one case, a witness said Ongwen ordered his troops to cook and eat civilians.

The defence, however, says it is considering several arguments including that Ongwen is suffering from post-traumatic stress syndrome. His lawyers also maintain he was acting under duress, as he lived under the constant threat of being killed by Kony and his commanders.

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A last-minute defence bid on Tuesday to have the hearings delayed for medical reports was denied by the judges.

Observers say Ongwen's trial raises deep questions about how to prosecute crimes involving children who were subjected to years of abuse.

"Dominic Ongwen's past experience as a child soldier is not a defence in itself," said Isabelle Guitard, from Child Soldiers International.

"It cannot exonerate him of the responsibility of having committed war crimes and crimes against humanity as an adult," she said.

Ongwen surrendered himself to US forces in 2015. But Kony remains at large with about 150 followers hiding out in the jungles of the Central African Republic.

Source: Al Jazeera News and Agencies