KHARTOUM - One international peacekeeper was killed and two were wounded in Sudan's troubled Darfur region when armed men ambushed their convoy, an official with the joint U.N./African Union force said on Tuesday.

The killing underlined the insecurity that persists in the region despite a flurry of diplomatic efforts to find an end to the six-year conflict.

A group of up to eight unknown armed men opened fire on peacekeeping soldiers and police as they escorted a minibus carrying civilian workers in El Geneina on Monday evening, force communications chief Kemal Saiki said.

Saiki said he would wait until the dead man's family had been informed before releasing details of his nationality and unit. The attackers also stole one of the three vehicles in the UNAMID convoy, he added.

Law and order has collapsed in Darfur since mostly non-Arab rebels took up arms against the government in 2003, demanding better representation and more development for the region.

Khartoum mobilised troops and mostly Arab militias to crush the uprising, unleashing a wave of violence that Washington and activists call genocide. Sudan's government denies the charge.

Estimates of the resulting death toll range from 10,000, according to Khartoum, to up to 300,000 according to U.N. humanitarian chief John Holmes.