A United Nations spokesperson confirmed on Tuesday that four peacekeepers belonging to the United Nations-African Union Mission in Darfur (UNAMID) have been kidnapped by unknown gunmen in the restive western Sudanese region of Darfur.

"I can confirm this," Martin Nesirky said. "UNAMID is working closely with officials for their safe return."

An anonymous UNAMID source told Xinhua on Tuesday that the four South African peacekeepers, two male and two female, were stopped by some 10 gunmen when they were driving from their working site to their private accommodation near Nyala, the capital city of the South Darfur state, on Sunday.

The source quoted witnesses as saying that the four policemen were forced to step off their vehicle at gunpoint.

No armed group in Darfur has made contacts with the UNAMID to claim responsibility for the kidnapping, the source noted.