The Democratic Republic of Congo’s army seemed to be on the way to a rare victory.

Having poured in 20,000 soldiers and pummelled the hilltops with artillery, it had inched last week past rebel strongholds high in the green hills of North Kivu.

United Nations peacekeepers, civil society organisations and much of the country had rallied in support of the government offensive, hoping that the last flames of a lingering war could be extinguished, and Congo’s vast potential would be tapped. Even the Bush administration in Washington had given a tacit green light, along with other western countries frustrated at the recalcitrance of the last significant rebel redoubt opposing the Kinshasa government.

Then the rebels hit back, with small, mobile groups attacking a brigade headquarters. Although vastly outnumbered, they precipitated a humiliating rout that has called into question multi-billion dollar international and United Nations efforts to rebuild the Congolese state, and dealt a huge political setback for the country’s elected President, Joseph Kabila.

The collapse of the government offensive showed how years of international diplomacy, the deployment of a 17,000 UN peace force, and the holding of elections a year ago have yet to resolve the regional conflict playing out in Congo’s east.

The rebels are led by Laurent Nkunda, a dissident ethnic Tutsi general who fought for a Rwandan-backed rebellion during Congo’s 1998-2003 war. He is in part the product of the ethnic rivalry that has flowed into Congo from its neighbours, Rwanda and Burundi. When other factions in Congo bought into the peace process Mr Nkunda refused a job in the new army.

Instead the general, who has been accused of war crimes, says his men are fighting to defend ethnic Tutsis against Hutu militias still roaming Congo’s east, nearly 14 years after they fled there after participating – in many cases – in the Rwandan genocide.

In the past few days, UN peacekeepers, who have been providing government troops with logistical support, have been forced to step in to prevent a further rebel advance.

Dozens of government soldiers were killed in the fighting. Their comrades, meanwhile, appear to have lost, sold or given away much of their ammunition. The road down from the mountains was littered with the uniforms of deserting troops.

An eyewitness in Minova, near where the battles took place described the retreat: “They arrived in small groups, armed but not all in uniform. They looked exhausted, hungry, and angry. They complained of betrayal, saying they had been shot at by soldiers sent to relieve them. Some of them stole cattle and goats from villages they passed.”

Having voted in their millions last year for Mr Kabila’s promised peace, 800,000 traumatised Congolese are on the move again in a fresh refugee crisis. Along the way villagers tell harrowing stories of forced recruitment, arbitrary killings and rape.

“I have lived through the last two wars and thought it had finally ended,” said Mama Rose, an ageing lady forced to flee from one makeshift roadside camp to another. “But, as you can see, this hell continues.”

President Kabila had pushed for a military solution. He stood to gain immeasurably from victory at a time that his stock both at home and abroad was at its lowest. Now, however, with his army’s morale in tatters, he has been forced to call a peace conference.

He is not alone in having difficult questions to answer. The UN mission in Congo (MONUC) was established in 1999, and has since become the world’s largest peacekeeping operation.

Throughout it has struggled to determine how to help resurrect the Congolese state, and how far it should go in supporting an army responsible itself for large scale abuse. It has also been beset by scandals.

MONUC helped Congo’s army plan the latest operation and transported men and ammunition to the frontline. But, unlike late last year when Indian soldiers blocked a rebel offensive, killing hundreds, diplomats say New York refused this time to give the blue helmets permission to take part in fighting.

This has soured relations with the government.

“We planned operations together and they said they would support us with aircraft, APCs and men,” said Col Delphin Kahimbi, deputy commander of Congolese forces in North Kivu. “But, on the day, they did nothing. They just observed the spectacle.”

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