Nuclear bomb blueprints and manuals on how to manufacture weapons-grade uranium for warheads are feared to be circulating on the international black market, according to investigators tracking the world’s most infamous nuclear smuggling racket. Alarm about the sale of nuclear know-how follows the disclosure that the Swiss government, allegedly acting under US pressure, secretly destroyed tens of thousands of documents from a massive nuclear smuggling investigation. The information was seized from the home and computers of Urs Tinner, a 43-year-old Swiss engineer who has been in custody for almost four years as a key suspect in the nuclear smuggling ring run by Abdul Qadeer Khan, the Pakistani metallurgist who in 2004 admitted leaking nuclear secrets and is under house arrest in Islamabad. The Khan network trafficked nuclear materials, equipment and knowhow to at least three countries: Iran, Libya, and North Korea. President Pascal Couchepin stunned his Swiss compatriots last week by announcing that the Tinner files, believed to number around 30,000 documents, had been shredded. The extraordinary move, prompting demands for a parliamentary inquiry, was warranted to prevent the documents ‘getting into the hands of a terrorist organisation or an unauthorised state’, according to Couchepin. […]