KHARTOUM (Reuters) - Up to 6,000 child soldiers, some as young as 11, have been recruited by rebels and government forces in Sudan’s Darfur conflict, the United Nations said.

Teenage fighters in the back of a vehicle at an undisclosed location in Sudan's Western Darfur region, April 18, 2008. REUTERS/Stuart Price/Albany Associates/Handout

Youngsters have repeatedly been seen carrying weapons, even though Sudanese law and international agreements banned the use of children in conflicts, the head of the U.N. children’s fund (UNICEF) in Sudan Ted Chaiban told reporters late on Monday.

Chaiban said UNICEF had evidence that all of Darfur’s main rebel groups used children, including the powerful Justice and Equality Movement (JEM) and the faction of the Sudan Liberation Army led by Abdel Wahed Mohamed Ahmed al-Nur.

Government forces, including the army, the police, Darfur’s Central Reserve Police and state-allied militias had also recruited under-18s, Chaiban said.

“All the armed factions and groups in Darfur have used children ... We have seen children in uniform and children carrying weapons with virtually all the forces,” he said.

“An 11-year-old in this sort of situation basically looses their childhood. It dehumanizes them.”

No one was immediately available for comment from Sudan’s armed forces or Darfur’s rebel groups.

U.N. agencies estimate more than four million people have been affected by almost six years of fighting in Darfur.

UNICEF says about half of those people are children.

“Of those roughly 700,000 were born since 2004, so all their life they have lived in an area that has been in conflict,” Chaiban said.

One former rebel group had agreed to demobilize its first 16 child soldiers in January, after a campaign by local children’s agencies and UNICEF, he said.

The faction of the Sudan Liberation Army led by Minni Arcua Minnawi -- the only rebel leader to sign a 2006 peace deal with Khartoum - had also identified another 100 to be released from military service later next year, he added.

Children’s rights groups were now hoping to sign similar demobilization deals with insurgents and had already secured agreements from the government to release children from service.

Most of the child soldiers identified by UNICEF and other groups were aged between 15 and 17, although some were as young as 11, said Chaiban.

Not all of them were directly involved in fighting, but international agreements banned all use of under-18s in conflict situations, even if they were only used as porters and in other support roles, Chaiban added.

UNICEF estimates there are a total of 8,000 child soldiers in Sudan, 6,000 in Darfur and the rest in southern Sudan -- which ended a two-decade civil war with the north in 2005 -- and the east of the country, the site of a low level insurgency against Khartoum.

Mostly non-Arab rebels took up arms against Khartoum in 2003, accusing the government of neglecting the remote western region. Sudan’s government mobilized mostly-Arab militias to crush the Darfur revolt.

Sudan denies accusations by activists that state-backed militias carried out mass killings and rapes during the counter-insurgency.