Hopes that Burundi's new government will bring a speedy end to the country's brutal civil war are on the verge of being extinguished, after Hutu rebels kidnapped two groups of school students within five days.

In the first attack, at the beginning of the week, dozens of schoolboys from a primary school in Burundi's eastern province of Ruyigi were abducted.

In the latest incident, a group of boys aged between 16 and 21 years old were kidnapped from high school in the northern Kayanza province.

President Buyoya heads the transitional government

The UN Children's Fund, Unicef, said it feared the rebels were conducting a campaign to force children to fight for them.

The mass abduction of boys and young men from schools is a new, brutal twist in an eight-year conflict, which has left an estimated 250,000 dead and caused widespread suffering among ordinary people.

The kidnappings, along with an upsurge of rebel violence in the east of the country, have left Burundi's new government looking vulnerable only days after its inauguration on 1 November.

Optimism

The mood then was one of cautious optimism. Hutu politicians had returned from exile to take part in Burundi's political experiment.

South African soldiers are in Burundi to protect Hutu politicians

Under the power-sharing deal brokered by the former South African president, Nelson Mandela, politicians from the minority, but traditionally ruling, Tutsi group and the majority Hutu community will govern together.

For the first 18 months, President Pierre Buyoya - a Tutsi - will be head of state. He will then make way for his Hutu vice-president, Domitien Ndayizeye. Elections are to be held within three years.

This novel arrangement follows years of protracted discussions between the various, feuding parties in the northern Tanzanian town of Arusha.

But Nelson Mandela's "Made in Africa" deal has a major flaw.

Rebels

The Arusha peace process never involved the two main Hutu rebel groups. As a result, the Forces for the Defence of Democracy (FDD) and the National Liberation Front (FNL), have no stake in the power-sharing agreement.

Hutus and Tutsis have shared out cabinet posts

So Burundians now have a new government, but not what they crave most: an end to the war.

The renewed violence since 1 November is a signal that the rebels have not been swayed from their campaign by the presence of Hutu politicians at the top level of government.

A spokesman for the FNL group told the BBC last week that his leadership did not want ministerial positions - it wanted control of the army.

The rebels see the Tutsi-dominated army, which has also been accused of grave human rights violations against Hutus, as their principle enemy.

However, Burundi's Tutsis would fear for their own safety if the nation's army was commanded by Hutus.

Fears of genocide - a repetition of what happened in neighbouring Rwanda, when 800,000 Tutsis and moderate Hutus were slaughtered - are never far from the surface.

What would tempt the rebels to the negotiating table is unclear.

Analysts say surprisingly little is known about the workings of the two main groups. In the case of the FDD, it is not even clear who is in charge at the moment. It is, therefore, extremely difficult to initiate meaningful negotiations.

Strategy

However, one of the international mediators in the conflict, Jan Van Eck, met the rebels recently in South Africa.

He was convinced that they would be interested in a ceasefire if only the right process could be put in place to bring them on board.

The new government has to find a way of dealing with the rebels if it is to survive.

In the run-up to 1 November, the new Hutu vice-president, Domitien Ndayizeye, told BBC News Online that it would be "catastrophic" if a ceasefire deal was not put in place soon.

But if the violence in the countryside continues, with thousands fleeing their homes and scores of children being abducted, the tensions within the new team will begin to surface.

Politicians from across the spectrum, including extremists from both sides, are represented in government.

Much will depend on how the two men at the top, President Buyoya and Vice-President Ndayizeye, collaborate.

In the coming days, politicians may well reflect that the easy part was forming the government. Working together, to find a way of bringing peace to a shattered country, will be far more difficult.