In 1981, Dirk Coetzee, Jan Viktor and Jac Buchner began Vlakplaas, a parliamentary hit squad, with 16 police officers.
The existence of the unit was first revealed publicly in 1988 on the eve of the execution of Almond Nofomela. Before his execution, Nofomela confessed to being part of the Security Police 'hit squad', which was headed by Dirk Coetzee. Coetzee admitted the existence of the unit in a November 1989 in an interview with Vrye Weekblad, and confirmed the story that Nofomela had told a Johannesburg weekly the previous year.
On strength of this and public pressure, the new state president, F.W. De Klerk, appointed a commission of inquiry, led by Judge Louis Harms, to investigate these allegations, and the operations of the Security Police and the Civil Co-operation Bureau (CCB).
The De Klerk government therefore set up the Harms Commission in Britain in 1990 to investigate these claims. In his testimony, Coetzee told the Harms Commission how he had watched his colleague murder the student activist Sizwe Khondile and the human rights lawyer Griffiths Mxenge. The Security Police closed ranks to lie and denounce Coetzee's revelations as fantasies, and Harms accepted their testimony. Coetzee was found to be an unreliable witness.
In Coetzee's later testimony before the Truth and Reconciliation Commission (TRC), Coetzee said that Khondile had been killed on 11 August 1981. After his release from detention, the police took Khondile to Komatipoort near the Mozambique border, where he was shot dead. His body was then burnt for more than seven hours to obliterate evidence.
Dirk Coetzee was granted amnesty by the Truth and Reconciliation Commission on 4 August 1997. In 1997, Eugene de Kock, a former commander of Vlakplaas, was convicted for attempting to murder Coetzee.