JOHANNESBURG — THE killing of at least 18 people in violence that erupted after the funeral of slain community leader Sam Ntuli in the strife-torn township of Tokoza Oct. 7 has put a four-week-old, nationwide peace accord under severe strain.In addition, 11 people were injured after the funeral rally attended by more than 10,000 supporters of the African National Congress (ANC). "The peace accord cannot deal with this kind of thing," says Graeme Simpson, acting director of the Project for the Study on Violence at Johannesburg's Witwatersrand University. "These kinds of attacks can only undermine confidence in the accord and reduce the chances of it working." The National Peace Committee, established under the terms of the accord, began setting up peace committees this week, but officials said implementation at grass-roots level would only begin next week. However, ongoing violence since the signing of the accord Sept. 14, has already damaged its credibility and drawn skeptical comments from community leaders. South African police spokesman Captain Eugene Opperman said it appeared that the occupants of an unidentified vehicle had driven around the township firing on mourners returning home from the funeral. No arrests have been made. Eye-witnesses said they had seen armed men in an unmarked vehicle conversing with armed black men in a white pick-up at the funeral ceremony before the killings. The men in the pick-up were later seen talking to a group of uniformed policemen, an eye-witness said. Mr. Simpson says that the type of violence that claimed Mr. Ntuli's life and those of the mourners was very difficult to control and would take time to disappear. "What the scandal about secret government funding of the Zulu-based Inkatha Freedom Party revealed was the existence of a culture of legitimized covert action in state structures. The extent to which the government is in control of its operatives in the security forces is now in question," Simpson says. Sue Vos, an Inkatha representative in the National Peace Committee and the National Peace Secretariat, said the events in Tokoza were "very disturbing. I don't know how we deal with it. What we have to confront is the existence of dehumanized killing machines in the townships." She said the inflammatory remarks of ANC Youth League President Peter Mokaba at the funeral could only further exacerbate the situation. At the funeral rally, Mr. Mokaba, called for the black townships to be made "ungovernable" again so that the government would be unable to dictate the pace of the liberation struggle. He urged ANC members not to be passive in the face of attack. "We expect them to return fire with fire and bullets with bullets," he said. Simpson said the peace accord could have an effect in the long-term by laying the foundations needed at the grass-roots level to stabilize the communities. ANC President Nelson Mandela, speaking at a separate function the night of Oct. 7 in the town of Boksburg where he was awarded the "Freedom of Boksburg" by mixed-race residents, blamed President Frederik De Klerk for the deaths. "De Klerk has let loose his hounds against the people," Mr. Mandela charged. "If he does not want the violence, why do the police act with such impunity?" Mr. De Klerk, speaking at a regional conference of the ruling National Party in Cape Province Oct. 7, said the government would not be intimidated by the ANC's "aggressive demands" which represented a threat to all South Africans and would lead to economic ruin. "Stability and a fundamentally sound value system ... are not negotiable. If we have to clash over that, we will clash." Ntuli, general secretary of the ANC-aligned Civics Association of the Southern Transvaal, was killed by unidentified gunmen near his Tokoza home nine days ago.