Sudan denies rebel attack

Thousands of civilians have been displaced by the war

The Sudan Government has denied accusations that it had killed 1,000 people in a major offensive against southern rebels.

Sudan's charge d'affaires in Nairobi Ahmed Dirdeiry said the reports were a figment of someone's imagination.

On Tuesday, rebel Sudan People's Liberation Army (SPLA) spokesman Samson Kwaje told the BBC that government helicopter gunships and Antonov bombers had attacked their positions around the town of Tam.

The reported fighting came just a week after the conclusion of a peace deal between the rebels and the Sudanese Government and a meeting in Uganda between the rebel leader John Garang and the Sudanese president.

But Mr Dirdeiry conceded that there had been some inter-clan fighting in the area.

The peace agreement outlined a plan for a referendum on possible secession for the south in six years but did not include an immediate cessation of hostilities.

Abducted

In a separate incident, a Kenyan aid worker and three of his colleagues were abducted, allegedly by government-backed militias.

The aid workers, employed by World Vision, were attacked early Monday at Waat, 820 kilometres (510 miles) south of the capital, Khartoum, said Alison Preston, a spokeswoman for the international Christian aid organization said.

Garang's has spent 19 years fighting northern rule

Two of those missing are Germans.

Reverend John Sudan of the Southern Sudan Operation Mercy aid organisation told the BBC that it has confirmation that the attacks on Tam took place and that tens of thousands of people have fled.

The scene of the fighting had been abandoned by the inhabitants, according to Reverend Sudan.

An aid worker backed up the claims that tens of thousands of people had fled the fighting.

"There is extremely heavy fighting," Dan Eiffe, a spokesman for Norwegian People's Aid (NPA) told Reuters news agency in Nairobi.

President Omar al-Bashir and SPLA rebel leader John Garang met at the weekend in Kampala for talks with President Yoweri Museveni of Uganda.

On Monday, US Assistant Secretary of State Walter Kansteiner said that fighting had significantly declined since the deal was signed in Kenya 10 days ago.

The SPLA told the BBC that the fighting in Upper Nile did not put the peace agreement at risk but that it reserved the right to retaliate.