KHARTOUM, Jan. 9 (Xinhua) -- The United Nations Mission in Sudan (UNMIS) on Saturday expressed concern over the escalating tribal violence in southern Sudan over the past couple of weeks where over 150 people have been reportedly killed and many more injured and displaced.

In a statement, Ashraf Jehangir Qazi, the UNMIS chief and the special representative of the UN secretary-general in Sudan, urged the southern Sudanese government to investigate these incidents and to redouble efforts to help de-escalate the rising wave of violence in the region.

"UNMIS offered to send peacekeeping troops to be present to help protect civilians during the rotations of SPLA (the Sudan People's Liberation Army, the military wing of the Sudan People's Liberation Movement) companies that were involved in confrontations with civilian cattle-keepers in Akot, near Rumbek, in late December and early January," Qazi said.

He added that about 24 persons including SPLA soldiers and civilians were killed and many displaced during these clashes.

"In Atar, Jonglei State, UNMIS flew senior government officials into the area and helped to deliver government-provided humanitarian aid on the day of the attack during which several civilians were killed and an estimated 100 tukuls were burned. Humanitarian agencies are bringing further assistance to the victims in the days ahead," he said.

"In Wunchuei, Warrap state, where tens of people were killed in inter-tribal cattle raids late in December, UNMIS sent a team of peacekeepers to defuse tensions and help prevent reprisal attacks. The team also has representatives of humanitarian agencies to initiate a humanitarian needs, assessment on the ground especially for those who have been displaced due to the violence. Thousands have been reportedly displaced but these figures as well as those concerning the victims of the attacks still need to be verified," Qazi said.

"UNMIS will continue to work within its mandate and capabilities to help the southern Sudanese government deal with the rising violence in southern Sudan and to help protect civilians," the UN official announced.

In one of the bloodiest incidents in southern Sudan, fighters of the Nuer tribe attacked the Dinka tribe at the weekend, leaving some 140 people dead.

The fighting, purportedly over cattle, also left at least 90 wounded and several thousands head of cattle looted, local median reported on Thursday.

The fight took place some days ago, but reports emerged only after a UN security team visited the area by airplane four days ago, according to a news service affiliated with the UN Office for the Coordination of Humanitarian Affairs.