<P> Reforms and negotiations to end apartheid led to a backlash among the right - wing white opposition, leading to the Conservative Party winning a number of by - elections against NP candidates . De Klerk responded by calling a whites - only referendum in March 1992 to decide whether negotiations should continue . A 68 per cent majority gave its support, and the victory instilled in de Klerk and the government a lot more confidence, giving the NP a stronger position in negotiations . </P> <P> When negotiations resumed in May 1992, under the tag of CODESA II, stronger demands were made . The ANC and the government could not reach a compromise on how power should be shared during the transition to democracy . The NP wanted to retain a strong position in a transitional government, and the power to change decisions made by parliament . </P> <P> Persistent violence added to the tension during the negotiations . This was due mostly to the intense rivalry between the Inkatha Freedom Party (IFP) and the ANC and the eruption of some traditional tribal and local rivalries between the Zulu and Xhosa historical tribal affinities, especially in the Southern Natal provinces . Although Mandela and Buthelezi met to settle their differences, they could not stem the violence . One of the worst cases of ANC - IFP violence was the Boipatong massacre of 17 June 1992, when 200 IFP militants attacked the Gauteng township of Boipatong, killing 45 . Witnesses said that the men had arrived in police vehicles, supporting claims that elements within the police and army contributed to the ongoing violence . Subsequent judicial inquiries found the evidence of the witnesses to be unreliable or discredited, and that there was no evidence of National Party or police involvement in the massacre . When de Klerk visited the scene of the incident he was initially warmly welcomed, but he was suddenly confronted by a crowd of protesters brandishing stones and placards . The motorcade sped from the scene as police tried to hold back the crowd . Shots were fired by the police, and the PAC stated that three of its supporters had been gunned down . Nonetheless, the Boipatong massacre offered the ANC a pretext to engage in brinkmanship . Mandela argued that de Klerk, as head of state, was responsible for bringing an end to the bloodshed . He also accused the South African police of inciting the ANC - IFP violence . This formed the basis for ANC's withdrawal from the negotiations, and the CODESA forum broke down completely at this stage . </P> <P> The Bisho massacre on 7 September 1992 brought matters to a head . The Ciskei Defence Force killed 29 people and injured 200 when they opened fire on ANC marchers demanding the reincorporation of the Ciskei homeland into South Africa . In the aftermath, Mandela and de Klerk agreed to meet to find ways to end the spiralling violence . This led to a resumption of negotiations . </P>

Detail how the system of racial segregation was established in the south