NABANGA, Sudan (AP) – Ugandan rebel leader Joseph Kony has turned up at a neutral camp in southern Sudan as part of a truce to end 19 years of conflict in the east African nation, a rebel official said Sunday.

Kony, who is wanted by the International Criminal Court for war crimes and crimes against humanity, arrived at Ri-Kwangba camp, just 550 yards north of the border with Congo, said Martin Ojul, the head of the rebel team negotiating a peace deal with the Ugandan government. He gave no further details on when Kony appeared.

Kony joins his deputy, Vincent Otti, whose arrival at the camp was announced on Sept. 11. Otti is also wanted by the Hague-based court.

Some 3,500 fighters and 400 women and children are also at the camp, according to Capt. Sunday Ocaya, who is also part of the rebel Lord’s Resistance Army’s negotiating team.

U.N. officials estimate the rebels have kidnapped 20,000 children in the past two decades, turning the boys into soldiers and the girls into sex slaves for rebel commanders. Otti has told U.N. officials the group would be willing to hand over the women and children.

The rebels, notorious for cutting off the tongues and lips of innocent civilians during the insurgency, signed a truce with the government late last month.

The deal calls for rebel fighters to gather in largely uninhabited areas across the border in southern Sudan, where they will be protected while a broader peace deal is negotiated.

Under the truce, the rebels should gather at two points in southern Sudan by Tuesday.

If both sides reach a comprehensive deal, it will be a major breakthrough in pacifying the volatile region comprising northern Uganda, eastern Congo and southern Sudan.

Rebels from all three nations operated across the borders with impunity for decades until a peace accord halted Congo’s civil war in 2003 and southern Sudanese rebels joined Sudan’s government in 2005.

Earlier this year the ICC pressed Uganda, Sudan and Congo to hand Ugandan rebel suspects over for trial. However, earlier this month, Otti said a comprehensive peace deal could be threatened by the international arrest warrants and President Yoweri Museveni has promised not to turn the suspects over in return for an end to the insurgency.

Human rights groups have condemned Museveni’s amnesty offer, but the president argues peace is more important than an international trial.

The Lord’s Resistance Army was formed from the remnants of a northern Uganda rebellion that began in 1986 after Museveni, a southerner, overthrew a brutal military junta.

Kony mixed northern politics with religious mysticism, declaring himself a Christian prophet fighting to rule this country of 26 million people by the Ten Commandments.