A Mossad secret service document leaked to Al Jazeera's Investigative Unit reveals that in 2010 Israel obtained stolen South African anti-tank missile technology.

South African intelligence covered it up. Years later, when two men charged with stealing the plans were put on trial in South Africa, prosecutors failed to release the full information of Israel's involvement.

Journalists who covered the case were fed a false account of events, and reported that Israelis had been offered the materials but " were not interested ", and had dismissed the black market salesmen as "a joke".

However, an Israeli secret service cable shows that Israeli businessmen had indeed been interested, had taken the salesmen seriously, likely purchased the blueprints and then apparently passed them on to the Mossad.

The Spy Cables include a top-secret reply to a South African request for Israel's intelligence service to return the purloined blueprints.

In it, Mossad says that "in light of the strong cooperation" between the two countries' intelligence services "we can, at least, return the missile plans to you".

But they did so on the condition that an Israeli citizen involved in the affair would "not be prosecuted or involved in legal issues".

It appears South Africa agreed to those terms because no Israeli has been directly involved in legal issues since.

Stolen missile plans

In the August 2010 Mossad cable, classified secret and titled "Macopa Missile Plans - Response", Mossad refuses to investigate how Israel got hold of the stolen plans.

The Mokopa air-to-ground missile system is manufactured by the state arms manufacturer Denel and named after the Setswana word for the feared Black Mamba snake.

But the cable offers Mossad's assistance in recovering the documents.

"Further to your request regarding the Macopa Missile Affair [sic], please note that our service has no authority to carry out investigations on Israeli territory," the Mossad writes. "However, In light of the strong cooperation between our services, and our sincere desire to assist you, we have examined ways in which we can, at least, return the missile plans to you."

But there is a condition: "Since, according to the information you relayed to us, an Israeli citizen, Mr Yitzhak Talia [sic], is involved in this affair, we would appreciate receiving confirmation from the competent authority that the Israeli citizen will not be prosecuted or involved in legal issues in South Africa concerning this affair, before we relay the plans to you."

"The information we will relay to you about this matter is classified intelligence and therefore should not be used in legal proceedings".

The Spy Cables do not explain how "Yitzhak Talia" is involved. But court documents mention a "Yitzchak Talyah aka Edward Henry Taljaard" and suggest he was shown the missile plans, but that his involvement went no further.

Two found guilty

The details come from a case in Pretoria, in which two men were tried for their role in the Mokopa Missile Affair. They were arrested two years earlier in an elaborate sting operation.

Danie Steenkamp, a former Senior Technician at Denel, pleaded guilty to two charges under South Africa's Protection of Information Act. He was sentenced to five years in prison.

Anthony Viljoen, the managing director of a company that worked with Denel, pleaded guilty to one charge under the Protection of Information Act and one under the National Conventional Arms Control Act.

He struck a plea bargain and became the state's witness, eventually walking free with a five-year suspended sentence and a fine of 500,000 Rand ($45,000).

The court papers say the two men met when Viljoen was repairing a missile trolley for Denel, and concocted a plan to sell the missile technology that included an offshore company any bank accounts in Mauritius.

The legal record shows that between January 2008 and January 2009 Steenkamp showed documents, models, objects and information about the Mokopa Missile to several people, including a "Yitzchak Talyah aka Edward Henry Taljaard" and "other persons unknown to the state (including the State of Israel)".

Steenkamp was accused of being "intent on showing and selling" the materials to "whomever wanted to buy," including "a foreign state or a hostile organisation".

One court document says that a mitigating factor in Viljoen's case was that "the attempts to sell this technology did not materialize and the state was aware of this transaction from an early stage."

However, the document leaked to Al Jazeera suggests that court was not told what the South African intelligence services knew: that that the Mokopa blueprints had, in fact, been in the hands of a foreign state.

According to court documents, a third accomplice, Johan Grundling, had travelled to Israel in the early stages of Steenkamp and Viljoen's attempts to sell the missile plans.

In March 2010, the record shows that Grundling shot himself dead while under police supervision in his own home pending his arrest, after police and fraud investigators had raided his house as part of a separate investigation into a multimillion-dollar tax fraud.

Grundling's connection with the Mokopa missile affair, and the transfer of the missile plans to Israel remains unclear.

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