12 January 1984
On 12 January 1984, a strong delegation of African National Congress (ANC) National Executive Committee (NEC) members arrived at Caculama, the main training centre of the ANC’s military wing, Umkhonto we Sizwe(MK) in the town of Malanje, Angola. Normally, such a visit by the ANC leadership, including the President Oliver Tambo would have been prepared for weeks, before they arrive. The emergency visit by the ANC leadership followed the refusal by MK combatants to go into counterinsurgency operations against the forces of the Union for Total Independence of Angola (Unita) in the civil war in Angola and defied the security personnel of the ANC. The combatants decided to mutiny, strongly by shooting randomly into the air. According Searchlight South Africa, it was pointed out to all the commanding personnel in the area that the shooting was not meant to endanger anybody's life, but was meant to be an appeal to the ANC leadership to attend  to the desperate problems facing our organization. The order by the combatants was that, only Tambo, Joe Slovo the chief-of-staff of the army and Chris Hani, then the army commissar, would be welcome to attend to these issues.
References

Ketelo B, Maxongo A, Tshona Z, Massango R. and Mbengo L. (July 1990), ‘A Miscarriage of Democracy: The ANC Security Dept. in the 1984 Mutiny of Umkhonto We Sizwe’, from Searchlight South Africa, Vol 2. No 1. (No. 5), [Accessed: 07 December 2011]