The processing system found at Tradefin, an engineering and manufacturing company in Vanderbijlpark, outside Johannesburg, had been designed and built over three years. It was then tested, painstakingly dismantled and packed into 40-foot containers, factory records show.
Daniel Jacobus Van Beek, director of South Africa's counter-proliferation office, participated in the raid and called the scheme "one of the most serious and extensive attempts" to breach international nuclear controls. He estimated that the 200 tons of equipment was worth about $33 million.
Khan, a German-trained metallurgist, used stolen designs and a shadowy network of European suppliers in the 1980s to build the Pakistani plant where uranium was enriched for that country's first atomic bomb.
A decade later, he resurrected the network to sell nuclear technology on the world market. Secrecy surrounding the Khan ring began to unravel last December, when Libya announced that it was giving up its effort to build an atomic bomb.
As part of a deal negotiated with the U.S. and Britain, Libya disclosed evidence that Khan and his associates had sold Tripoli $100 million worth of technology over 10 years, including designs for a nuclear warhead.
That information led to the immediate shutdown of a Malaysian operation that manufactured centrifuges and sent investigators scrambling to follow up on evidence that the ring had sold enrichment technology to Iran and North Korea.
Under international pressure, Pakistan forced Khan to confess on national television that he had sold the country's nuclear secrets. Pakistani President Pervez Musharraf pardoned Khan immediately. Investigators from the IAEA and the U.S. have not been allowed to interview the scientist, who is still revered in Pakistan.
As a result, investigators say they are still struggling to uncover the extent of the network.
In the months before police raided Tradefin, one participant said he had pressed his alleged accomplices to "melt down" the equipment, burn the designs and destroy computer files, according to statements to police. But when investigators arrived with search warrants, the evidence was intact.
Enrichment involves feeding gaseous uranium known as uranium hexafluoride into an array of slender centrifuges, which spin at ultrahigh speed to transform the gas into weapons-grade material.
