&A: Sudan's Darfur conflict
Many thousands of displaced people are in need of relief supplies
The United Nations Security Council has approved a 26,000-strong peacekeeping force to replace the 7,000 African Union (AU) observer mission struggling to protect civilians in Sudan's western province of Darfur.
But the exact make-up and deployment date for this beefed up force is still to be determined.
In the meantime, more than 2m people are living in camps after fleeing more than four years of fighting in the region and they are vulnerable without peacekeepers.
Sudan's government and the pro-government Arab militias are accused of war crimes against the region's black African population, although the UN has stopped short of calling it genocide.
Peace talks involving the government and most of the myriad rebel groups have recently resumed, but until the new UN-AU force deploys in Darfur the prospects for an end to violence look remote.
How did the conflict start?
The conflict began in the arid and impoverished region early in 2003 after a rebel group began attacking government targets, saying the region was being neglected by Khartoum.
The rebels say the government is oppressing black Africans in favour of Arabs.
Darfur, which means land of the Fur, has faced many years of tension over land and grazing rights between the mostly nomadic Arabs, and farmers from the Fur, Massaleet and Zagawa communities.
There are two main rebel groups, the Sudan Liberation Army (SLA) and the Justice and Equality Movement (Jem), although both groups have split, some along ethnic lines.
More than a dozen rebel groups are now believed to exist. Most will attend the talks in Libya, but one key leader, Abdul Wahid el-Nur, is boycotting the talks until the conflict ends.
What is the government doing?
It admits mobilising "self-defence militias" following rebel attacks but denies any links to the Janjaweed, accused of trying to "cleanse" black Africans from large swathes of territory.
Refugees from Darfur say that following air raids by government aircraft, the Janjaweed ride into villages on horses and camels, slaughtering men, raping women and stealing whatever they can find.
Many women report being abducted by the Janjaweed and held as sex slaves for more than a week before being released.
The US and some human rights groups say that genocide is taking place - though a UN investigation team sent to Sudan said that while war crimes had been committed, there had been no intent to commit genocide.
Sudan's government denies being in control of the Janjaweed and President Omar al-Bashir has called them "thieves and gangsters".
After strong international pressure and the threat of sanctions, the government promised to disarm the Janjaweed. But so far there is little evidence this has happened.
Trials have been announced in Khartoum of some members of the security forces suspected of abuses - but this is viewed as part of a campaign against UN-backed attempts to get some 50 key suspects tried at the International Criminal Court in The Hague.
What has happened to Darfur's civilians?
Millions have fled their destroyed villages, with some 2m in camps near Darfur's main towns. But there is not enough food, water or medicine.
The Janjaweed patrol outside the camps and Darfuris say the men are killed and the women raped if they venture too far in search of firewood or water.
The Janjaweed are accused of 'ethnic cleansing'
Some 200,000 have also sought safety in neighbouring Chad, but many of these are camped along a 600km stretch of the border and remain vulnerable to attacks from Sudan.
The refugees are also threatened by the diplomatic fallout between Chad and Sudan as the neighbours accuse one another of supporting each other's rebel groups.
Chad's eastern areas have a similar ethnic make-up to Darfur.
Many aid agencies are working in Darfur but they are unable to get access to vast areas because of the fighting.
How many have died?
With much of Darfur inaccessible to aid workers and researchers, calculating how many deaths there have been in the past three years is impossible.
What researchers have done is to estimate the deaths based on surveys in areas they can reach.
The latest research published in September 2006 in the journal Science puts the numbers of deaths above and beyond those that would normally die in this inhospitable area at "no fewer than 200,000".
The US researchers say that their figures are the most compelling and persuasive estimate to date. They have made no distinction between those dying as a result of violence and those dying as a result of starvation or disease in refugee camps.
Accurate figures are crucial in determining whether the deaths in Darfur are genocide or - as the Sudanese government says - the situation is being exaggerated.
Have there been previous peace talks?
Lots.
KEY REBEL PLAYERS
SLM: Minni Minnawi's faction signed 2006 peace deal
SLM: Abdul Wahid Mohammad Ahmed al-Nur's faction rejected peace deal
Jem: Khalil Ibrahim, one of the first rebel groups, rejected deal
Rebel negotiator: Suleiman Jamous
SLM Unity: Abdallah Yehia
UFLD: recently formed umbrella group including SLM commanders
Other breakaway SLM commanders: Mahjoub Hussein, Jar el-Neby and Suleiman Marajan
There are estimated to be more than 13 rebel factions in Darfur
The leader of one SLA faction, Minni Minawi, who signed a peace deal in 2006 after long-running talks in Nigeria, was given a large budget, but his fighters have already been accused by Amnesty International of abuses against people in areas opposed to the peace deal.
The other rebel factions did not sign the deal.
There has been a dramatic increase in violence and displacement since the deal was signed.
Amid international threats of sanctions for those refusing to attend, many rebel groups briefly attended preliminary talks with the government in Libya in October 2007 - but there is little hope of a quick breakthrough.
Is anyone trying to stop the fighting?
About 7,000 African Union troops are deployed in Darfur on a very limited mandate.
Experts say the soldiers are too few to cover an area the size of France, and the African Union says it does not have the money to fund the operation for much longer.
The recent killing of 10 AU soldiers by a rebel group in northern Darfur has highlighted the need for the new force to be deployed - but at the same time makes it harder for the AU and UN to secure pledges of troops.
The new, larger joint UN-AU force should be in place by early 2008 - if international support is forthcoming - and be better equipped and with a stronger mandate to protect civilians and aid workers.
But until recently, Sudan resisted strong Western diplomatic pressure for the UN to take control of the peacekeeping mission and their attitude to the deployment and its mandate remains ambiguous at best.
Some say even this new 26,000 force will not be enough to cover such a large, remote area.
Others point out that peacekeepers cannot do much unless there is a peace to keep.
They say the fighting can only end through a deal agreed by all sides, which has yet to materialise.
