KHARTOUM (Reuters) - Fighting has erupted between government forces and rebel groups in Sudan's Darfur region, rebels and U.N. peacekeepers said on Tuesday, days after peace talks stalled over a planned referendum.
People from both sides were killed when the clashes broke out over the weekend, the rebel groups said. Sudan's army was not immediately available to comment.
Darfur has been racked by violence since 2003 when mostly non-Arab rebels took up arms against Khartoum, which responded with a brutal counter-insurgency campaign.
Violence has fallen from its peak in 2003 and 2004 but a surge in attacks since December has forced tens of thousands to flee. Peace talks in Qatar have stalled over Khartoum's plan to hold a referendum on the administrative make-up of Darfur.
The joint African Union-U.N. mission in the region said its peacekeepers witnessed fighting near the Umm Baru area in Darfur on Tuesday, where they had earlier observed armed rebels and a buildup of government forces.
A spokesman for the Justice and Equality Movement (JEM), the most powerful Darfur rebel group, said government-backed militia forces attacked its soldiers at the weekend with vehicles and followed that up with air strikes in the coming days.
JEM last week said it suspended talks with the government in Doha, accusing Khartoum of making a unilateral decision to hold the referendum on Darfur.
A JEM soldier was killed in fighting on Saturday, spokesman Gibreel Adam said. He said the group had been working in an alliance with other rebel groups in the area -- the Sudan Liberation Movement factions loyal to Minni Arcua Minnawi and Abdel Wahed Mohamed al-Nur.
Nur's spokesman Ibrahim al-Helwu confirmed the fighting and said the rebel groups had seized government vehicles and soldiers during the clashes.
"There is heavy fighting in the northern areas," al-Helwu said. "There was a big number of casualties."
The International Criminal Court has issued an arrest warrant for Sudan's President Omar Hassan al-Bashir on charges of masterminding genocide and war crimes in Darfur. The United Nations says as many as 300,000 people have died during the conflict. Khartoum puts the death toll at 10,000.
(Reporting by Deepa Babington)