A dirty tricks smear campaign is being waged against South Africa's top prosecutor and Scorpions boss Bulelani Ngcuka, apparently in retaliation for the investigation into alleged corruption in the multi-billion rand arms deal.

Ngcuka this week vowed to clamp down soon on what he termed "comrade criminals", referring to the involvement of suspects with the anti-apartheid struggle.

He said they were intent on maligning him to divert the thrust of investigations into the arms deal, through a spate of "scurrilous" speculation about him.

Weekend Argus is aware of highly defamatory false rumours about Ngcuka, apparently emanating from Durban, which have on investigation been found to be baseless and unpunishable.

In a case that has been published, a newspaper reported later last week that Ngcuka, the National Director of Public Prosecutions, was about to resign to join mining giant De Beers.

Ngcuka said it had also been alleged that he was part of some underhanded deal in which he would join a mining house in exchange for concessions obtained from his wife Phumzile Mlambo-Ngcuka, the Minister of Minerals and Energy. He said the story was a fabrication.

He said this week was clearly a "concerted and orchestrated" campaign of rumour and innuendo aimed at discrediting him to deflect Scorpion investigations of top people mostly connected with investigations into possible wrongdoing in the multi-billion rand arms deal.

Ngcuka vowed to "sting" those responsible within a matter of weeks. "We are not Scorpions for nothing", he said.

"But in doing so we will act within the confines of the law. No amount of malicious rumour-mongering will deter us from doing our job. We will arrest these people very soon."

While he was not prepared to name names, he said some of those involved were "well connected ....criminals masquerading as comrades". But he would not hesitate to act against them.

Intelligence sources said they had "picked up on the radar" what appeared to be a smear campaign against Ngcuka.

In as exclusive interview, Ngcuka said it was unfortunate that the newspaper which published the report had allowed itself to be used by faceless people whose agenda was questionable. The whole story was a fabrication.

"I did not speak to the Sunday World nor have I tendered my resignation, therefore I am not about to join De Beers, not because it is not a great company, which I believe it is. It (joining De Beers) would create major conflict of interest for me and also because my wife, Phumzile, is the Minister of Minerals and Energy."

Questioned on why these faceless people would attempt to discredit him and why De Beers was named, he said: "Firstly, the choice of De Beers is not accidental. De Beers serves a dual purpose because it is in the sector that my wife works. They are trying to discredit my wife and myself and to a certain extent our government. I think that my wife is doing a good job in spearheading reforms in the mining sector. An impression has now been created that in promoting these reforms she has been motivated by self-interest."

More important, the rumour campaign was aimed at "destabalising my organisation in the mistaken belief that I am the Scorpions".

Ngcuka said the tactic was motivated by the belief that the campaign would "disrupt our work and we will discontinue our investigations".

"They are very, very wrong. They underestimate our unshakeable commitment to the cause of justice and the rule of law."

Asked if he had decided to resign before the apparent rumour campaign was started, Ngcuka said: "My agenda is not determined by criminals. For me the question is not whether I leave or not but how I do so.

"I have always strived to do my job to the best of my ability. I will leave when I want to and on my terms."

Ngcuka said he would not be "chased away by criminals masquerading as comrades no matter how well connected or rich they might be".

With acknowledgements to Andre Koopman and the Weekend Argus.