NEW YORK, Aug 25: The Central Intelligence Agency (CIA) enlisted a family of Swiss engineers to help abort an underground supply network of Pakistani nuclear scientist Dr Abdul Qadeer Khan as well as undermine the Libyan and Iranian nuclear programmes, the New York Times reported on Monday.

The Times said that the Swiss engineers, Friedrich Tinner and his two sons, were accused of having deep associations with Dr Khan, acting as middlemen in his dealings with rogue nations seeking nuclear equipment and expertise.

Over four years, the CIA paid the Tinners $10 million, some of which was delivered to them in a suitcase stuffed with cash, the newspaper said citing unnamed officials.

In return, the engineers delivered a flow of secret information that helped end Libya’s nuclear weapons programme, reveal Iran’s atomic efforts and undo Dr Khan’s nuclear supply network.

The Tinner family, according to the Times, also played an important role in a clandestine US operation to funnel sabotaged nuclear equipment to Libya and Iran.

Friedrich Tinner began working with Dr Khan in the mid-1970s, using his expertise in vacuum technology to help him develop atomic centrifuges.

But in 2000, the CIA recruited his son, Urs Tinner, who eventually persuaded his father and younger brother to join him as moles.

As part of their services, the engineers helped the CIA to sabotage atomic gear bound for Libya and Iran, the report said.

But the case has been hampered by the destruction of relevant documents, which was done, according to Swiss officials, to prevent their falling into terrorist hands. But the newspaper pointed out that the real reason for the destruction of files was pressure from the CIA which feared that its ties with the Tinners would be exposed.

The files were of particular interest not only to Swiss prosecutors but also to international atomic inspectors working to unwind the activities of Dr Khan. The NYT said analysts studying the Khan network worried that by destroying the files to prevent their spread, the Swiss government might have obscured the investigative trail. It is unclear who among Dr Khan’s customers — a list that is known to include Iran, Libya and North Korea, but which may extend further — got the illicit material, much of it contained in easily transmitted electronic designs.