South Africa has seen more than its share of carnage, but nothing in recent times to quite match the horror of last week’s massacre. At least 39 people, including 24 women and children, died in the assault on the township and an adjoining squatter camp, 40 miles southwest of Johannesburg. South African President F. W. de Klerk expressed “shock and revulsion. " But when he attempted a visit to Boipatong only days later, he was besieged by an enraged mob of 3,000 blacks who shouted, “Go away, murderer!” and tried to surround the presidential motorcade before 15 armored vehicles cut them off. After de Klerk’s entourage sped off, police opened fire on the crowd. Eyewitnesses said as many as three people died-two of them as they fled clouds of tear gas-and at least 20 were wounded. De Klerk later hinted ominously to reporters that he might consider reimposing the state of emergency that his government lifted two years ago.

His words inflamed the African National Congress, which days earlier had launched a campaign of strikes, protests and boycotts aimed at breaking an impasse in constitutional talks with the government. “We charge F. W. de Klerk and his government with complicity in this slaughter,” declared Cyril Ramaphosa, the ANC’s secretary-general. The ANC has often accused South African security forces of instigating violence in black townships through covert support of the Inkatha Freedom Party, a Zulu-dominated rival nationalist movement. As usual, both the government and Inkatha denied any responsibility. A spokesman for the Ministry of Law and Order suggested that the ANC itself was to blame-contending its “mass action” campaign against the government had raised tension in the townships to “unacceptable levels.”

But eyewitnesses gave credence to the ANC’s claims. Minutes before the attack, a prominent Methodist minister reported to a police colonel that he had received calls from local residents warning of imminent trouble. Instead of protecting the township, say Boipatong residents, police fired tear gas to disperse local youths manning barricades at its entrances. Minutes later, the Zulu-speaking mob began its rampage. Some residents said that whites took part in the assault. One woman told reporters she heard a man shout in Afrikaans, " Open the door,” then caught sight of a white man’s forearm as she hid under her bed.

The attack nearly snapped already strained relations between the ANC and the government, further jeopardizing talks that began between the two parties last December over a new constitution. Those talks deadlocked last month over issues related to the size of the majority needed in an elected assembly to approve a constitution. The dispute masks profound differences between the government and the ANC. The ANC is committed to black majority rule in South Africa, confident that it would win any future election based on the principle of one person, one vote. De Klerk is prepared to share power with the ANC but not to give it up entirely. He wants to build cheeks and balances into a new constitution that would give the white minority effective veto power.

Not since February 1990, when de Klerk announced his momentous decision to legalize the ANC and release Nelson Mandela, has the political climate in South Africa been so filled with distrust. Eyewitness accounts accusing police of ferrying Zulu-speaking hostel dwellers to Boipatong support old ANC charges against de Klerk. Either he has lost control of his security forces, ANC officials argue, or they are doing his bidding by undermining the liberation movement. Failure to mount a swift and aggressive investigation of the massacre, and to bring its perpetrators to justice, will only feed growing suspicions of a cover-up. Since the breakdown of talks, the country’s townships have been bracing for an explosion on a par with the upheavals of the past two decades. Many South Africans fear that the massacre in Boipatong may be the spark that will set off another conflagration.