Rumangabo, DR Congo  - After seven days marked by about- faces, a dramatic betrayal and hopeful talks of peace, the conflict in eastern Democratic Republic of Congo has taken another twist.

On Tuesday in the town of Rumangabo, 40 kilometres west of Goma, the Congolese army held a ceremony to bring its bitter enemies, Tutsi rebel group the National Congress for the Defence of the People (CNDP), into its ranks.

The CNDP late last year routed the Congolese army during a major offensive that sent 250,00 civilians fleeing.

It captured large swathes of eastern DR Congo in the process and reignited the 1998-2003 conflict, which has killed over 5 million Congolese and displaced at least 1 million in the vast, mineral-rich country.

The ceremony to bring the CNDP into the army was cancelled, however, after most of the rebels abandoned the ceremony and drove away in trucks, singing and laughing as Congolese officials huddled to discuss the developments.

Several dozen CNDP rebels remained behind but seemed unsure what to make of the integration process.

"I think things are moving too fast," a young rebel named Innocent told Deutsche Presse-Agentur dpa.

The CNDP did not explain its decision to leave, but international observers at the scene spoke of anger over decisions to split up rebel brigades and concern over the status of detained CNDP leader Laurent Nkunda.

The events mark the latest twist in a dramatic seven days in the war-torn African nation.

The intrigue began last Thursday, when 4,000 Rwandan troops entered DR Congo to engage the Hutu Democratic Forces for the Liberation of Rwanda (FDLR), dramatically detaining Nkunda, a staunch ally, in the process.

Nkunda was taken into custody as he fled into neighbouring Rwanda.

The Congolese government has formally requested he be extradited to face war-crimes charges.

His fate remains clouded in mystery with Rwandan authorities saying that the rebel leader was not in prison but rather "in a safe location."

The surprise arrest, which some feel was part of the deal that allowed Rwanda to enter DR Congo and tackle the Hutu militia, sent shockwaves through the region.

After deposing Nkunda, Rwandan troops joined with government and former rebel forces in operation Umoja Wetu (Our Unity), making a bee-line for FDLR strongholds, sending troops west and north from Goma, the provincial capital.

Thirteen rebels have reportedly been killed in fighting in the Masisi and Lubero regions.

Aid agencies have also warned that the Rwandan offensive could lead to another refugee exodus and the killing of innocent civilians.

The FDLR, many of whom fled across the Congolese border following the 1994 Rwandan genocide in which 800,000 Tutsis and moderate Hutus were slaughtered in 100 days, hold positions throughout the volatile eastern DR Congo.

The events mark the third time Rwanda has sent troops onto Congolese soil to fight the militia, who staged numerous raids over the border in the years following the genocide.

During his rebellion, Nkunda said he was fighting to protect Congolese Tutsis from FDLR attacks.

With Nkunda sidelined, the CNDP's new leader Bosco Ntaganda, who is wanted for war crimes by the International Criminal Court, brokered a deal and said he would fold his fighters back into the army.

Despite Tuesday's setback, the integration programme is expected to proceed, Congolese government officials said.

MONUC, the United Nations peace keeping operation with 17,500 soldiers in the region, was initially sidelined from the planning of the operation, but on Tuesday said it would provide logistical support.

Analysts say that the UN faced the unpleasant decision of being shut out of the operation and not fulfilling its mandate of protecting civilians or collaborating with a wanted war criminal in Ntaganda.

Alan Doss, the UN special envoy for the region, said that MONUC would also step up patrols in areas where fighting was anticipated and to try and repatriate FDLR fighters back to Rwanda.

"The first preference is to try and get [the FDLR] to disarm and leave in a peaceful way," he told dpa. "I think there's an opportunity now, I hope everyone will seize it, to finally close this chapter."

History, however, suggests that DR Congo is not yet out of the woods, as this is not the first time the Congolese army has welcomed its enemies in an attempt to create a national army.

At the end of the 1998-2003 conflict, warring parties united and joined the national army. But the union didn't last long.

Nkunda broke ranks in 2004 and retreated with 4,000 soldiers to eastern DR Congo, from where he launched his rebellion and ultimately helped create the current crisis. (dpa)