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GENEVA, Jan 18 (Reuters) - Up to 700,000 people are expected to be uprooted by the violence in Mali, including 400,000 who could flee to neighbouring countries in the coming months, the United Nations refugee agency said on Friday.
French, Malian and African forces are confronting an Islamist rebel alliance that includes al Qaeda's North African wing in a military operation that began last week.
"We believe there could be in the near future an additional 300,000 displaced inside Mali and up to 400,000 additional displaced (refugees) in neighbouring countries," UNHCR spokeswoman Melissa Fleming told a news briefing in Geneva.
Some 147,000 Malians have already fled to countries including Mauritania, Niger, Burkina Faso and Algeria since the crisis began last year. Some 229,000 Malians are already internally displaced within Mali.
"We have been hearing horrific accounts from refugees in the neighbouring countries," Fleming said.
"They report having witnessed executions, amputations, and they say also large amounts of money being offered to civilians to fight against the Malian army and its supporters," she said.
"Disturbingly we are also hearing accounts that there are children among the rebel fighters."
(Reporting by Stephanie Nebehay; Editing by Angus MacSwan)