The Truth and Reconciliation Commission (TRC) on Monday heard that the SA Defence Force prepared a counter-attack force of 50 to 60 tanks, helicopters and jet fighters at Zeerust in case Botswana retaliated during a raid on ANC members in Gaborone in 1985.
In the cross-border raid on houses informers said were occupied by Umkhonto weSizwe cadres, 14 people were killed - among them women, children and foreigners.
The TRC was hearing an amnesty application from the last of 12 former security branch policemen involved in the raid.
Amnesty applicant Manuel Olifant said: "Why we had so much military personnel was that should anything go wrong with Botswana forces, we'd have been able to stand and fight."
The attack was led by ex-Rhodesian Selous Scouts working for the South African security branch.
Olifant told the amnesty committee that security branch Lieutenant Willem Coetzee paid him R1 500 for his part in the killings.
Olifant, who is now a superintendent in the SA Police Service, said he and an informer identified safe houses used by Umkhonto weSizwe cadres in Gaborone from addresses given to them by Coetzee.
Olifant said he was not asked to check if there were women or children also living in the target houses. He also claimed he did not know that all those living in the houses would be killed in an attack.
Relatives of the victims and former exiles attending the Johannesburg hearing have accused Olifant of lying during his application. - Sapa