(Agencies)
Updated: 2008-02-05 09:02

N'DJAMENA, CHAD - Chadian rebels renewed their assault on the capital of this oil-rich country Monday, and tens of thousands of people were fleeing as gunfire crackled and artillery shells exploded.

Hours after the rebels resumed their attack following an overnight retreat, the United Nations gave the green light for France and other countries to help the government. France, with more than 1,000 soldiers backed by fighter jets in its former colony, indicated it was ready to take on the insurgents.

Three days of fighting in N'Djamena are believed to exact a heavy toll, leaving the city's streets littered with bodies and burned out tanks. The violence is further destabilizing a swath of Africa that is home to hundreds of thousands of refugees and borders the war-ravaged Darfur region of Sudan.

There are also fears a wider regional conflict could be ignited - Chadian officials have repeatedly accused neighboring Sudan of supporting the rebels, and one senior general threatened to attack Sudan in retaliation. Sudan denies involvement.

A force of 1,000-1,500 insurgents equipped with pickup trucks mounted with machine guns arrived on the capital's outskirts Friday after a three-day push across the desert from Chad's eastern border with Sudan. They penetrated the city early Saturday, reportedly trapping President Idriss Deby in his palace.

The government launched a fierce counterattack Sunday, strafing rebel positions with helicopter gunships and bombarding them from tanks.

By early Monday, the rebels had pulled back, but they insisted it was a tactical withdrawal to give people a chance to flee - and the battle resumed in the afternoon.

"Fighting and shelling has started again in N'Djamena," said Helene Caux, a spokeswoman for the UN refugee agency.

The death toll was not known. But "the fighting was heavy, the weapons used were heavy," French military spokesman Capt. Christophe Prazuck said. "Probably many people were injured or killed."

Hundreds of people have been wounded, most believed to be civilians hit by stray bullets, said Isabelle Defourny, head of Chad operations for the French organization Medecins sans Frontieres, or Doctors without Borders. The fighting made it difficult to reach them.

She said doctors had treated about 70 wounded people since Saturday.

Tens of thousands of people were fleeing N'Djamena, across the Chari River into Cameroon, the organization said.

The city was chaotic, said Christophe Droeven, the head of Catholic Relief Services who was evacuated Sunday.

"This is a real battle," he said by telephone from Paris. "We saw burnt tanks, burned out cars, people stealing vehicles, some people looting houses, people running with TVs on their heads."

The worst fighting was on Saturday when "for between six and seven hours they were shooting around us with everything - tanks, choppers, heavy machine guns."

The violence endangers a US$300 million (about euro200 million) global aid operation supporting millions in the Central African nation. The United Nation's World Food Program said Monday that the fighting also could disrupt delivery of food to some 420,000 refugees from Darfur and Chadians displaced by violence.

At the United Nations, the Security Council strongly condemned the rebel attack and called "upon member states to provide support" to Chad's government.

There was no immediate reaction from Paris. But French President Nicolas Sarkozy, speaking before the Security Council issued its statement, said France and the European Union would send troops only with the council's approval.

"We must avoid a conflict in Chad by supporting the legitimate government," Sarkozy told reporters during a visit to Bucharest. "In no region should weapons be a way to come to power."