When the conflict began in September, it was between the Zairean army and a group of ethnic Tutsis in eastern Zaire known as the Banyamulenge. Related to the Tutsis who dominate both Rwanda and Burundi, they migrated some 200 years ago to what is now eastern Zaire from the ancient Tutsi kingdom of Rwanda.
But during the past week a localised dispute has escalated into a war between two nations. Following artillery exchanges between Rwandan and Zairean troops, Rwandan forces crossed the border and engaged in street fighting in the strategic town of Goma, capital of North Kivu province. Rwanda denies arming the Banyamulenge, or having any territorial ambitions of its own, but its Tutsi-led regime will find it increasingly difficult to maintain this stance.
Also involved are Hutu militias and soldiers of the former Rwandan army, who fled to eastern Zaire among more than a million Rwandan Hutu refugees. They are now fighting alongside the Zairean army against the Banyamulenge and the Rwandan army.
Why are there so many refugees in Zaire?
More than a million Rwandan Hutus poured over the border into eastern Zaire in 1994. They were fleeing the victorious Tutsi rebels who invaded the country from Uganda to overthrow the previous Hutu-led regime and put an end to its campaign of genocide, in which at least half a million Tutsis and many moderate Hutus died.
The refugees have stayed in Zaire because they fear retribution if they return home. Some - the extremist militias and the government officials who led the genocide - have every reason to be afraid. There are also tens of thousands of Hutu refugees from Burundi who have fled ethnic conflict in their country.
What started the latest fighting?
The Banyamulenge say they are being persecuted by the Zairean authorities. They lost the right to vote in 1981, and have been increasingly treated as foreigners in South Kivu province. Earlier this year their Tutsi kinfolk in North Kivu were all but driven out by local Hutus and Rwandan Hutu militiamen from the refugee camps. Since Tutsis are widely resented for their superior wealth, the Zairean army and local politicians did not intervene.
Seeing what lay in store for them, the Banyamulenge in South Kivu started arming. The crunch came in September when the provincial deputy governor announced the Banyamulenge had a week to leave "or be hunted down as rebels". They took their cue and launched a pre-emptive strike. Rwanda says it has no interest in helping the Banyamulenge, but wants to empty eastern Zaire's refugee camps, from where the rump of the former Rwandan army and exiled Hutu militias have been launching guerrilla attacks on Rwanda. These forces are supporting the Zairean army because their survival depends on it: in defeat they risk being driven back to Rwanda and the punishment awaiting them there.
What is the difference between a Hutu and a Tutsi?
They are two distinct peoples. Hutus are descended from Bantu-speaking migrants who came from west Africa more than 2,000 years ago. The Tutsis are of Nilotic origin and came southwards, herding their cattle before them, about 400 years ago. Hutus make up about 85 per cent of the populations of Rwanda and Burundi, and Tutsis only 15 per cent, but the Tutsi pastoralists established a feudal caste system with the Hutu cultivators as vassals. Centuries later, Tutsis tend to dominate commerce and most of the institutions of their countries.
The stereotypical Tutsi has finer features, lighter skin and is taller than the Hutu, though centuries of inter-mixing have lessened the physical differences. However, political agitation has exacerbated their "apartness"; genocide and war have deepened the divide even further.
Could this split Zaire?
Zaire has been heading towards anarchy and dismemberment for a long time. One of its provinces, Shaba in the south, has a strong degree of autonomy, even its own currency, though it has failed to break away completely. The strongman who has held it together is President Mobutu Sese Seko. But he has lost the support he once enjoyed from the West, and has been receiving treatment for prostate cancer in Switzerland for nearly three months. The latest reports indicate that the cancer has spread to his bones.
Back home, the political vacuum is deepening. If Zaire's poorly-trained army is defeated in the east and President Mobutu remains out of action much longer, things could disintegrate still further. A Tutsi victory in eastern Zaire could inspire other insurgencies and, before long, secessionist movements could spring up all over the sprawling country of more than 250 tribes.
What would it take to get the refugees home?
A lot of convincing. The United Nations High Commissioner for Refugees has made repeated attempts to persuade them to go home. On occasions, the Zairean authorities have tried to intimidate them into going back. But only a trickle have returned.
The Rwandan government has repeatedly said it only takes issue with those who took part in the genocide. The current crisis might persuade many refugees that they would be better off taking their chances in relatively peaceful Rwanda. But the extremists, those who wielded machetes and ordered mass killings, will never want to go home as long as a Tutsi-dominated regime and army are in control.
How serious is the threat of starvation?
Very, say the United Nations and aid workers, if relief supplies cannot reach the region, most of which is inaccessible due to fighting. Nearly 750,000 refugees and civilians are on the move, beyond the reach of help. Many are heading for Mugunga camp, near Goma, the only one still functioning. But the camp already has more than 500,000 people, and services are stretched to the limit.
A more imminent danger than starvation is disease due to inadequate sanitation and water supplies. Tens of thousands could die if cholera breaks out in the camps.
Can we do anything?
There are diplomatic moves to resolve the conflict, but it is becoming increasingly clear that outside intervention is essential. The US and the European Union are pushing for an African peacekeeping force, funded largely by the West. There has been a lot of talk but no decisions and, even if one is eventually made, it might be too late for countless thousands. Such a force could not impose peace, but it could provide safe havens for refugees and civilians. The most pressing task is to isolate or evict the armed extremists bent on destabilisation, and to persuade all sides to enter talks.
Richard Dowden, page 21