BENTIU: Sudanese jets launched a fresh bombing raid on a key South Sudan town Monday, dashing hopes that a withdrawal of Southern troops from a contested area would end weeks of fighting.

Warplanes dropped several bombs on Bentiu, capital of the oil-rich border state of Unity, killing at least one child and wounding several civilians, an AFP reporter who witnessed the bombing said.

"This is a serious escalation, and a violation of the territory of South Sudan... I think it is a clear provocation," Mac Paul, the South's deputy director of military intelligence said.

"The bridge and the market were bombed," Paul said, adding that at least one was killed. Ten civilians, including three children, were brought to Bentiu hospital.

"One boy was severely wounded... the dead have not been brought to us, they are still left where they died," said hospital director Joseph Tanyuan.

Bombs targeting a key bridge in the town landed some 50 metres away from the AFP correspondent, prompting heavy bursts of gunfire from Southern soldiers hoping to shoot down Khartoum's warplanes.

In the market, stalls were on fire and large plumes of grey smoke rose high into the air, as screaming civilians ran in panic.

Several shouted angrily that the South had been made to withdraw from Heglig, but that the attacks on civilians were still continuing.

One charred body of a small boy was seen by the AFP correspondent, while market traders said that three civilians had been killed, although that could not be immediately verified.

"Yesterday they (Sudan) attacked us, and then today they continue to attack us, what is next?" said the South's Lieutenant General Obuto Mamur.

Southern officials claimed Sudan's troops had pushed across the contested border on Sunday before being repelled after heavy fighting, although it was impossible to verify exactly where the clashes took place.

Southern troops were digging into positions fearing renewed ground attacks by Sudan, he added.

"We do not attack, but our soldiers are in their positions," Mamur said.

Kamal Marouf, a Sudanese army commander, claimed in Heglig Monday that more than 1,000 South Sudan troops were killed in the clashes.

"The numbers of killed from SPLM are 1,200," Marouf said in an address to around 2,000 of his soldiers in the town. Sudan has not said how many of its own soldiers died in the operation.

The main oil processing facility in Heglig -- providing half of Sudan's crude -- was heavily damaged, an AFP correspondent there reported.

Violence in Heglig was the worst since South Sudan won independence in July after a 1983-2005 civil war in which an estimated two million people died.

The United Nations said Sunday the entire population of Heglig had fled the unrest, with thousands of displaced civilians living in the open.

The South pulled out from Heglig after international pressure, but is calling on Khartoum to withdraw its troops from the contested Abyei region, which it seized last May forcing 110,00 civilians to flee southwards.

Tensions have mounted over the disputed border and other unresolved issues, raising concerns in recent weeks about the possibility of a wider war. AGENCIES