NAIROBI, Kenya (AP) -- A militia hunting down members of a specific ethnic group targeted and killed at least six South Sudanese aid workers over two days during a new bout of violence close to the South Sudan-Sudan border, the U.N. said Tuesday.
Two of the victims were murdered in the town of Bunj on Tuesday while another three died in an ambush, the U.N. said. A sixth aid worker was killed Monday and a seventh is missing and presumed dead, the U.N. said. It condemned "in the strongest terms" the Upper Nile state killings by the Mabanese Defense Forces.
Ethnically targeted attacks have been a hallmark of the violence coursing through South Sudan since December. All of the murdered aid workers belong to the Nuer ethnic group, the same group that former vice president and current rebel leader Riek Machar belongs to.
The violence comes in a region where more than 100,000 refugees fleeing another conflict -- in the Nuba Mountains of Sudan -- have sought shelter and safety. The violence threatens to bring Sudan into South Sudan's internal conflict, an advocacy organization warned Tuesday.
The U.N.'s refugee agency, UNHCR, said the outbreak of violence the past 48 hours is compromising the security of the more than 100,000 Sudanese refugees who fled clashes in Sudan's Blue Nile state.
"These ethnically targeted attacks on unarmed aid workers will have a very drastic and adverse impact on the operations of humanitarian partners who have been providing food, shelter and other relief items to over 127,000 refugees from Sudan for over three years," the U.N. said.
The U.N. has no military or police presence in Bunj, the epicenter of the violence, but the U.N. said it dispatched a unit of peacekeepers in four armored personnel carriers to Bunj to protect U.N., humanitarian personnel and civilians inside United Nations facilities
Peace talks between South Sudan's government and rebel fighters restarted on Monday in Ethiopia, but no breakthroughs have been announced. South Sudan saw ethnically motivated violence spiral out of from the capital last December after President Salva Kiir accused Machar of initiating a coup, a charge he denies.
The new border clashes threaten to draw Sudan and its rebel groups into South Sudan's own civil war, said Nuba Reports, a media outlet that advocates for residents in Sudan's Nuba Mountains who are caught in a conflict with Sudanese troops. The group said as South Sudan's conflict creeps north, it is slowly merging with the war between South Sudan's government and the group called the SPLA-North.
One reason there is a threat of wider violence is that Kiir blames Sudan for supplying arms to Machar's rebel forces, said Nuba Reports.
Because of the latest violence near the border, the delivery of aid supplies to refugees was suspended, UNHCR said. Food distributions were to take place Monday but had to be canceled.
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