NEW YORK A United Nations peacekeeper was killed on Friday in Sudan's main oil region when shells struck a United Nations logistics base, a U.N. spokesman said.
The slain peacekeeper was from Ethiopia, U.N. spokesman Kieran Dwyer said, adding that two other Ethiopian peacekeepers were injured in the shelling.
He said the U.N. base in Kadugli, capital of South Kordofan state, is used to support the U.N. peacekeeping force deployed in the Abyei region disputed by Sudan and South Sudan.
It was not immediately clear who was responsible for the attack, but fighting in the area between rebels and the army has intensified in recent months.
Sudan blamed the attack on an umbrella group of insurgent forces that aims to topple President Omar Hassan al-Bashir.
Foreign Ministry spokesman Abubakar El-Saddiq said the attack was part of the "criminal behavior" of the Sudanese Revolutionary Front, which attacked an army base in South Kordofan last month.
The U.N. said earlier this month that more than 60,000 people had fled a town in the state after an attack by insurgents in April.
U.N. Secretary-General Ban Ki-moon condemned the attack and extended his condolences to the family of the slain peacekeeper and to the government of Ethiopia.
He urged Sudan and the Sudan People's Liberation Movement-North to suspend hostilities and resume ceasefire negotiations to end the conflict in Southern Kordofan and Blue Nile States.
Sudan has accused South Sudan of backing rebels in South Kordofan and other border areas in fighting that began shortly before South Sudan declared independence in July 2011.
Both countries firmly deny backing militias in each other's territory. Earlier this week, Sudan said it will close oil export pipelines with South Sudan within two months unless Juba gave up support for insurgents operating across their shared border.
"It is essential that the government of Sudan and Sudan People's Liberation Movement-North immediately cease hostilities, and resume ceasefire negotiations," Dwyer said in a statement.
(This story was fixed to correct quote in last paragraph to remove reference to government of South Sudan)
(Reporting By Michelle Nichols in New York and Khalid Abdelaziz in Khartoum; Writing by Maggie Fick; Editing by Michael Roddy)