The Nigerian police units, totaling 280 personnel, are specially trained in high-risk operations. Officials say the deployment of the Formed Police Units is in response to a call from U.N. Secretary-General Ban Ki-moon to increase the number of troops on the ground in the war-ravaged Darfur and counter the escalating rebel violence in the region, the United Nations reported.

The two Nigerian police contingents, along with units from Bangladesh, Indonesia and Nepal, bring the total number of the specially trained Formed Police Units in Darfur to five. Officials say the Nigerian Formed Police Units will be deployed in West Darfur.

Ban has called for the U.N.-AU mission to have "19 Formed Police Units once at full strength," the release said.