The United Nations is attempting to confirm reports that more than 3,000 villagers were massacred in communal violence in South Sudan.
If the death toll is confirmed - UN officials and South Sudanese army officers have yet to do that, saying they were still collecting information from the conflict zone - it would be one of the deadliest clashes in South Sudan in recent memory.
In the past two weeks, UN aircraft had been tracking an unusually large column of 6,000 to 8,000 heavily armed fighters from the Lou Nuer ethnic group as it advanced toward the town of Pibor, cutting a swath of destruction across the savanna.
Pibor is the hometown of the Lou Nuer's traditional rival, the Murle, and the two groups have been locked in a tit-for-tat cattle rustling feud for years, with the death toll steadily rising each round.
According to Joshua Konyi, the commissioner of Pibor County and a Murle, 2,182 women and children and 959 men were killed, 1,293 children were abducted and 375,186 cows were stolen.
"We've been counting the bodies," Mr Konyi said by telephone from Pibor last night. "It's really a genocide. If you come, you will see."
He said Lou Nuer fighters had mercilessly hunted down civilians who were cowering in the bush. Other Murle leaders said hundreds of women had been chased into a river, where they drowned.
Earlier this week, UN officials had a much lower estimate, describing a death toll "in the tens, if not the hundreds" and saying that several corpses had already been unearthed.
UN peacekeepers had tried to stop the fighters from storming the town of Pibor, but when it was clear that the peacekeepers and government soldiers were vastly outnumbered, Pibor's residents were advised to flee.
As many as 50,000 people scattered across the area. At first, UN officials believed that the early warnings had saved many lives.
"At this stage, it's very difficult to get an accurate picture," Kouider Zerrouk, a UN spokesman in South Sudan, said yesterday.
"We're not in a position to confirm any figures, and we're in the process of assessing their validity."
The Pibor area is one of the most rugged and cut-off parts of South Sudan, surrounded by thick forests and swamps.With thousands of fighters still roaming around and many roads inaccessible, UN officials said they would not know the full extent of the violence for several more days.
New York Times