South African spies suspect China was behind a series of break-ins at a major nuclear facility, and that agents stole technology in order to gain the advantage in a new kind of nuclear power generation, according to secret documents leaked to Al Jazeera’s Investigative Unit.
But public comments and diplomatic communications by the South African government on the incident avoided any reference to alleged Chinese involvement.
The intelligence documents contradict claims made by the South African government and nuclear officials dismissing the 2007 incidents at the Pelindaba Nuclear Research Center as "a piece of random criminality" and a simple "burglary attempt". 
THE SPY CABLES
A leak of hundreds of secret intelligence papers from agencies all over the world, offering a glimpse into the murky world of espionage.
Al Jazeera's Investigative Unit is publishing a selection of the documents and the stories contained within them. 
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They also debunk the theory reported by a number of US media outlets, that the thieves may have been part of a "terrorist group" trying to "build a weapon".
South Africa’s spies conclude that China had dispatched the two groups of armed men  who cut through a fence surrounding the nuclear facility, disabled alarms and shot a man who interrupted them.
He was left in a critical condition, while the attackers escaped with a laptop computer stolen from a control room. They were never caught.
China then moved ahead in its own development of the new technology that was being researched at Pelindaba, known as a Pebble Bed Modular Reactor, despite starting its project a year later than South Africa - which abandoned its own pebble-bed plans in 2010, citing a lack of investor interest.
"Random criminality"
Abdul Minty, South African representative at the International Atomic Energy Agency,  dismissed the break-in as "a burglary attempt," while the head of the national nuclear corporation NECSA played it down as just "a piece of random criminality".
However, a secret South African intelligence briefing on counter espionage dated 2009 offers a fuller explanation.
It says South Africa had been developing Pebble Bed Modular Reactor (PBMR) technology, for which the Pelindaba facility would be the fuel plant.
 "Several foreign intelligence services have shown interest in the progress of South Africa’s PBMR research and development," the secret briefing from the State Security Agency explained. 
 "It is suspected that the thefts and break-ins that took place… were to advance China’s rival project called Chinergy," the briefing continued. "China has developed and are one year ahead of PBMR project though they started several years after."
Terrorism hype
Following the break-ins in 2007 at Pelindaba Nuclear facility outside Johannesburg, some media suggested the culprits might have been interested in obtaining nuclear material to create a bomb.
"Your next story should be about nuclear terrorism," George Tenet, former director of the US intelligence agency, the CIA, had reportedly told CBS' 60 Minutes producer Michael Karzis as they dined together at a Washington, DC, restaurant.
"It's not a question of if terrorists will detonate an atomic bomb somewhere in the United States but merely a question of when," Tenet told Karzis.
The news magazine programme followed the CIA man’s advice, and by late 2008 the investigative programme had a story - about the break-in at a nuclear plant in South Africa. CBS gave the piece the dramatic title, "Assault on Pelindaba" and warned viewers the tale was "the kind of thing that keeps presidents up at night".
What happened "would make a hell of a movie," presenter Scott Pelly told viewers. It was almost the perfect Hollywood story of a lone "hero" who "saved the day" and averted nuclear disaster by taking on a group of armed men.
The programme made it clear whom they thought the attackers might be. "Worst-case scenario, bad guys getting their hands on weapons grade uranium," wrote producer Karzis.
Wikileaks
The break-in at Pelindaba also features in the Wikileaks release of US diplomatic cables .
A confidential US memo from January 2009 showed that the South Africans had also told the US government that they "attribute the November 2007 Pelindaba break-in to criminal - rather than terrorist - intent."
There was no mention of Chinese espionage. China is South Africa’s biggest trading partner, and Pretoria maintains close diplomatic ties with Beijing.
The Wikileaks cable also stated that the CBS exposé had left South Africa feeling "sensitive about its nuclear security" and the TV segment, which featured senior Department of Foreign Affairs and nuclear officials, had "got their back up".
The document concluded that, "this may make it more difficult for South African officials to pursue the US offer for assistance on enhancing the security of nuclear and radiological sites".