UNITED NATIONS (CNN) -- Another U.N. peacekeeper has been killed in the Darfur region of Sudan, the United Nations said Wednesday.
The death comes as U.N. Secretary-General Ban Ki-moon called efforts to resolve the five-year-old conflict in the region "deeply disappointing."
The slain peacekeeper's nationality was not immediately disclosed. U.N. spokeswoman Marie Okabe said he was shot and killed while on patrol in the territory, where Sudan's government has waged a brutal counter-insurgency campaign in response to a 2003 rebel uprising.
The latest attack follows the deaths of seven peacekeepers from the U.N.-African Union Mission in Darfur force in an ambush last week.
"Investigations are ongoing, and further information will be made available. UNAMID condemns all acts of violence against its peacekeepers," Okabe said.
The Security Council condemned last week's attack on UNAMID troops as "premeditated, deliberate and intended to inflict casualties" Wednesday.
In a presidential statement, the council said that attack involved more than 200 fighters "using sophisticated weaponry and tactics," and warned that attacks on peacekeepers can be considered war crimes under international law.
"The Security Council welcomes the U.N. investigation under way and the government of Sudan's statement to assist the U.N. investigation," the statement said. "It calls on the government of Sudan to do its utmost to ensure that the perpetrators of the attack are swiftly identified and brought to justice."
Concerns about the peacekeeping mission have also been fueled by Monday's decision by the head of the International Criminal Court to file genocide charges against Sudanese President Omar Hassan al-Bashir in connection with the Darfur campaign.
About 8,000 peacekeepers have been deployed to Darfur, Okabe said -- about 40 percent of the force's projected strength.
"The parties continue to pursue the path of military confrontation instead of dialogue," she said. "Deployment of UNAMID is still behind schedule. Sexual- and gender-based violence continues with impunity, and heightened insecurity and banditry has severely hampered the ability to provide life-sustaining humanitarian aid."
John Sawers, the British ambassador to the United Nations, said the Security Council is discussing whether to extend UNAMID's mandate for another year. But he said the absence of "any cooperation" by Sudan's government in Khartoum has complicated matters.