At least four persons are feared dead, as a Nigerian Air Force Mi-35 Helicopter on a training mission crashed on Monday afternoon south of Bama in Borno, Defence Headquarters said in a statement.   A statement, issued by Maj.-Gen. Chris Olukolade, the Director of Defence Information in Abuja on Monday, said the helicopter crashed because of technical fault.   

The statement did not state how many persons were on board but said investigations have commenced.