Sudan-South Sudan border: Clashes kill dozens in disputed Abyei region

More than 50 people, including United Nations peacekeepers, have been killed in attacks in an area disputed between South Sudan and Sudan, the United Nations has said.

It is the deadliest incident in a three-year-long spate of clashes in oil-rich region of Abyei.

Two armed groups raided Abyei on Saturday, local authorities said.

The day after, peacekeepers came under fire when transporting affected civilians to hospital, the UN said.

South Sudan and Sudan jointly administer Abyei, and both claim ownership to the region in a dispute that has remained unresolved since the South's independence in 2011.

The fighting at the weekend is reportedly linked to a land conflict between rival factions of the Dinka ethic group - the Ngok and Twic - from Abyei and South Sudan's Warrap state respectively.

According to a statement from the authorities in the Abyei Special Administrative Area, external, a group of "rebels" joined armed youths from the Twic faction and carried out a series of "barbaric coordinated attacks", starting on Saturday morning.

Forty-two people, mostly women and children, were killed on the first day of the attacks, the administration said.

Saturday's fatalities include a Ghanaian peacekeeper, the United Nations Interim Security Force for Abyei (Unisfa) said, external, in a statement calling for a "swift" investigation into the violence.

Unifsa also said that on Sunday, other peacekeepers came under fire "while transporting affected civilians from a Unifsa base to a hospital".

A Pakistani peacekeeper was killed, and "four uniformed personnel and one local civilian sustained injury", it said.

Unifsa's statement, released on Monday, added: "Currently, according to local authorities, 52 civilians have lost their lives, while 64 others are said to be gravely wounded."

According to the AFP news agency Rou Manyiel Rou, secretary general for the Abyei Special Administrative Area, said on Saturday that the violence was tied to a long-running "conflict between Ngok and Twic (Dinka)" communities.

The UK, Norway and the United States, the international trio that sponsored South Sudan's independence, said on Monday that they were "deeply concerned by the escalation of violence in recent months between communities living in and around" Abyei.

"All leaders who have influence with involved communities and who fail to use it to support peace are demonstrating their disregard for the interests of their people," the joint statement said, according to AFP.

The weekend's deadly attacks follow clashes in November last year that killed 32 people, including a UN peacekeeper.