The International Criminal Court will investigate the weekend massacre of more than 200 people in northern Uganda, a statement says.
Some 4,000 people had lived in the camp
The BBC's Will Ross says that not a single hut remains at the camp for displaced people near the town of Lira.
The army says it is pursuing the attackers, believed to be members of the Lord's Resistance Army.
For almost two decades the authorities have been fighting the LRA, which is known for its brutality.
Burying the dead
"The prosecutor of the ICC, Luis Moreno Ocampo, will investigate the crimes committed on Saturday 21 February 2004 in Barlonya camp, north-eastern Uganda," read a statement from the world's first permanent war crimes court.
Some 4,000 people had lived in the camp, which is now deserted, except for a few people who have returned to bury their dead, our correspondent says.
As the insurgents surrounded the camp, 26km (16 miles) north of Lira, many people ran to their grass huts and were burned as the insurgents torched their houses, said local MP Charles Angiro.
"It's a hopeless situation, we went there this morning with the Lira district police commander and physically
counted 192 bodies. The scene is terrible," he said.
Fifty-six people were taken to the hospital with burns, shrapnel and gunshot
wounds, one of whom died on Sunday, said Dr Jane Aceng, head of Lira hospital.
Altogether the conflict is said to have displaced at least one million people and the ICC has already said it will investigate the rebellion.
A rebel spokesman has denied responsibility for the attack.
Brigadier Sam Kollo told the BBC's Focus on Africa programme that those killed had been caught in crossfire.
The camp was being guarded by a local self-defence militia which was outnumbered and outgunned, an army spokesman said.
Major Shaban Bantariza said the LRA was trying to scare the militias into giving up their work.
"I've never seen in my life such a massacre... I saw in one hut alone a whole family members still burning," a Ugandan priest in Lira told the BBC.
The LRA, led by self-proclaimed mystic Joseph Kony, are known for kidnapping young children, to become fighters or sex slaves. The group has been based in lawless areas of neighbouring southern
The Ugandan army says the rebels attack the camps to divert its attention away from hunting the insurgents down in the bush.
The Ugandan army said 25 rebels were killed in a different area on Saturday.
However, while the army claims to be weakening the rebels, civilians remain extremely vulnerable, says the BBC's Will Ross, in the capital Kampala.
Newly recruited militias have so far been unable to defend the population, he says.