There's been fighting between rival factions of soldiers in Burundi after a coup was declared, but then denied by the government.
Military officials claim most of the country's capital Bujumbura is under the control of forces loyal to President Pierre Nkurunziza.
However, leaders of the attempted coup insist the city is in their hands.
Unrest started in Burundi after President Nkurunziza announced he would seek a third term in office.
A coup was announced by a former intelligence chief on Wednesday while the President was in Tanzania for talks.
He reportedly remains there in a secret location having been unable to return to Burundi.
Stephane Dujarric, spokesperson for United Nations Secretary-General Ban Ki Moon, says the UN is watching closely.
IN: "The secretary...
OUT: ...those concerns."
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