Rightists Lay Siege to S. Africa Talks : Violence: Armed whites storm negotiations site. Mandela charges that police were slow to act.

In a brazen attempt to thwart constitutional negotiations, several hundred white extremists stormed the talks site here Friday, waving shotguns and handguns, spray-painting slogans on the walls and assaulting black and white delegates.

The two-hour siege, the first direct attack ever on the forum debating the nation’s future, was a bitter reminder of the threat that the militant, well-armed right poses to a settlement in South Africa and to any future government controlled by blacks.

And, for the African National Congress, the government’s main black opposition, the reluctance of police officers to prevent the assault--or make a single arrest at the scene--was clear evidence of the need for joint, black-white control of the police force.

“The image of a lame-duck government is very difficult to avoid,” said ANC President Nelson Mandela.

If the demonstrators had been black, Mandela said he told President Frederik W. de Klerk, “hundreds of people would have been shot and killed on the spot.”

De Klerk, appearing on national television, said that “this despicable act” had posed “a grave risk” to negotiations. He vowed that those responsible would be arrested and denied “that police act differently when blacks are involved.”

But the two leaders, who are due to receive a joint award from the city of Philadelphia next week, promised to press ahead with negotiations.

“The aim of the right is to derail talks and prepare for civil war,” Mandela said. “That we cannot allow.”

Neither Mandela nor De Klerk was present when the assault happened. Constitutional Development Minister Roelf Meyer and ANC Secretary General Cyril Ramaphosa were among those who were at the talks.

The attack began in the morning when an armored truck crashed through the plate-glass front doors of the World Trade Center, which has been the venue for constitutional talks since December, 1991.

Police stood idly by as the hundreds of armed white protesters, many wearing the uniforms of the Afrikaner Resistance Movement (AWB)and its armed wing, roamed the halls and occupied the main debating chamber, where they sang hymns and painted “Eie Volk, Eie Land, “--One People, One Land--on the walls.

Government ministers and top black leaders, guarded by plainclothes police, hid behind locked doors inside the center until the demonstrators left, following a police agreement not to make any immediate arrests. Outside, several thousand rightists cheered and raised placards reading, “Stop phony negotiations,” “No to socialist slavery” and “De Klerk is ‘n verraier “--a traitor.

No shots were fired and only minor injuries were reported. But South Africans were shocked by the sight of several hundred whites easily taking over the hall that has become a symbol of hope for their country’s future.

The ANC called it “a full, frontal attack on the most basic principles of democracy.” And analysts saw it as the beginning of a more militant wave of protest from the right, whose leaders are demanding that negotiators agree to carve out an independent homeland for the white minority.

“The idea was to get in there,” said Keith Conroy, leader of the black-uniformed Iron Guards, the armed wing of the Afrikaner Resistance Movement. “We have got home to people inside (the hall) that talking isn’t enough. This showed that we mean business.”

But leaders of the Afrikaner People’s Front, a coalition of right-wing groups, apologized for the attack, blaming it on supporters who had “gotten out of hand.” They said the front had planned a peaceful demonstration, approved in advance by police, but that the swashbuckling AWB leader, Eugene TerreBlanche, broke ranks.

Many of the right-wing protesters outside the hall did not approve of the attack, which seemed likely to damage the credibility of right-wing groups that still sit at the bargaining table. But they said it indicated the growing frustration among whites who fear an ANC-led government and the loss of white privileges.

“If negotiations continue, the point will come where we’ll have no option but to fight,” said Wim de Wet, 41, of Brakpan, 23 miles east of Johannesburg. “We want our particular areas where we can be independent and where we can live as Christians and civilized people. We are not part of the Third World.”

Mandela asked “all decent Afrikaners” to repudiate the attack, and he noted that he has repeatedly said the ANC “is sympathetic to the demand of the right wing for self-determination.”

He also called for a day of nationwide protests next Thursday “in defense of democracy.”

Multi-party talks resumed after the siege ended, with negotiators continuing their search for agreement on April 27, 1994, as the date of the country’s first democratic elections. Delegates said the assault highlighted the need for an election date and a multiracial transitional council to oversee the police force.