WHEN night falls, there is an eerie quiet in the wide and deserted streets of this prosperous mining town 200 miles south of Johannesburg. ``Can you see a black man anywhere?'' asks burly Afrikaner Hennie Muller as he makes a sweeping gesture with his right arm.
``Not a black in sight,'' replies Jan Bezuidenhout, a stocky man in a khaki uniform with a 44 Magnum revolver in a leather holster at his side.
Mr. Bezuidenhout, who faces a murder charge for the death of a black man a year ago, is the commander of a white vigilante group known as Blanke Veiligheid (BV) or White Security.
BV leaders say they are prepared to work with ``conservative'' blacks - particularly Zulus - in countering what they call the radicalism and communism of the African National Congress (ANC).
``There will never be black majority rule in this country,'' says David Naude, a red-haired Afrikaner businessman who founded the organization.
He says that although the organization did not seek to import Natal's violence to the Orange Free State, it would not hesitate to fortify its ranks with Zulus to fight the ANC.
``It would be a natural alliance of conservatives,'' said Mr. Naude.
The BV vigilante group was formed six weeks ago to halt a protest march by black teachers. It is the latest in a proliferation of white right-wing groups determined to stop the advance of the ANC, legalized by President Frederik de Klerk two months ago.
``Since the unbanning of the ANC, there has been a lot of uncertainty in the town,'' said Mr. Muller, a mechanic who was once a member of the more extreme Afrikaner Resistance Movement (AWB) which denounces blacks, Jews, and English-speakers.
``Nelson Mandela was hardly out of prison for half an hour when he began advocating violence and vowing that the armed struggle would go on,'' said Muller. ``This has spread a lot of fear among the whites.''
Muller, the 43-year-old BV leader, was among 67 right-wing activists arrested by the police on March 9, when black protesters first took to the town's streets.
``I'm not a racist,'' he said. ``Our main target is the ANC. What you are seeing here is a conservative backlash against radical blacks and whites.''
He and his colleagues - they claim a membership of 3,800 out of a white population of some 58,000 - have vowed that a black demonstration will never happen again.
Disillusioned by what they regard as the neutralization of the police force, groups like these appear to have taken the law into their own hands, apparently enjoying wide support from the white communities in which they operate.
The 140,000 blacks in the nearby township of Thabong live in terror of the armed white patrols that stalk the streets of Welkom at night in pickup trucks. ``People are no longer free to walk about at night,'' says Mbulelo Bungwane, a regional official of the anti-apartheid National Union of Mineworkers.
Mnikelo Ndamse, a black miner, was beaten to death by white vigilantes here two weeks ago.
Tension has spread to the surrounding mines of the Anglo American and General Mining corporations, where about 150,000 black miners have been campaigning to end discrimination.
On March 20, blacks in Thabong staged a consumer boycott in the town to protest the detention of several youth activists. On the same day, a tornado swept through the white neighborhoods of the town and left hundreds of whites homeless. Looting of white homes by blacks increased the atmosphere of fear and racial tension.
The 600,000 or so white South Africans who voted for the right-wing Conservative Party in last year's general election are losing hope that they can ever win power through the ballot box. They appear to be turning to extra-parliamentary methods to halt a government they believe is bent on selling out the whites. In the Orange Free State, 46 percent of the white constituents voted for the Conservative Party.
Conservative Party leader Andries Treurnicht has backed a campaign to collect a million signatures to force another election by May 26.
Eugene Terre Blanche, flamboyant leader of the neofascist AWB, publicly ridicules the signature campaign from platforms in the country's conservative rural and mining towns. ``We are not seeking a million votes, but a million rifles,'' he thunders.
Sensing the right-wing groundswell for more extreme action, Dr. Treurnicht last week supported the formation of vigilante groups as a means of self-defense.
Welkom - the name means ``Welcome'' in Afrikaans - is today a microcosm of the conflict. White extremists are trying to halt Mr. De Klerk's reforms and his quest for negotiated political settlement with the majority.
A visit to Welkom this week showed that most of the members of the rapidly growing BV - which has also sprung up in surrounding towns - are Conservative Party supporters.
BV leaders spurn the more extreme methods of the AWB - who patrol the town in pickups and automobiles displaying red flags with the three-legged swastika - and apparently beat blacks indiscriminately.
Armed BV members' pickup patrols confront any blacks they see on the street as they make their way through the town's white neighborhoods at night.
They are contemptuous of what they see as the impotence of the regular police force.
Law and Order Minister Adriaan Vlok has branded the BV as a ``subversive alternative structure.'' ``I want to warn that alternative structures are illegal,'' he said on a recent visit here.
``Police don't have the manpower to perform the law-and-order function in Welkom any longer,'' said Muller, once a policeman himself.
He claims that policemen are leaving the force at the rate of more than 20 a day because they cannot cope with a legalized ANC. Poor pay and working conditions additionally contribute to the police exodus.
Muller vows that his organization will stop a planned April 21 march by black miners.
``We don't want this to develop into a racial war,'' says Mr. Bungwane.
``That would have a detrimental effect on building a nonracial future for South Africa.''