BERLIN, Oct. 11 -- German prosecutors said Monday they had arrested an engineer on suspicion that he helped Libya in its efforts to build a nuclear weapons program, eight months after the man was named by authorities in Malaysia as a key figure in a network that spread nuclear secrets around the world.
The man was arrested Thursday in the central German state of Hesse, according to the German federal prosecutor's office, which did not release his full name. Officials close to the investigation identified him as Urs Tinner, 39, a member of a Swiss engineering family that has drawn scrutiny from European authorities and nonproliferation experts for more than two decades.
In February, Malaysian officials identified Tinner as a middleman in a network that supplied Libya with gas centrifuge parts that could be used for the enrichment of uranium. That network, headed by Pakistan's top atomic scientist, Abdul Qadeer Khan, allegedly sold nuclear secrets to Libya, Iran and other customers and is the focus of a global investigation by the International Atomic Energy Agency and authorities in more than a dozen countries.
According to German and South African officials, who carried out recent arrests of alleged members of the network, those involved attempted to illegally deliver high-technology engineering equipment to Libya for its then-budding nuclear weapons program, drawing on companies in Germany, Malaysia, Spain, Switzerland, South Africa and the United Arab Emirates. Libya has since dismantled its weapons program under a deal negotiated with the United States and Britain.
German prosecutors said in a statement that they were preparing to charge Tinner, a Swiss citizen, with conspiracy to commit treason. A spokeswoman for the federal prosecutor's office declined to elaborate or give details.
Swiss export-control officials said Monday that they recently completed an inquiry into the business activities of Tinner and his family, based on the allegations made in February by Malaysian police. In a telephone interview, Othmar Wyss, spokesman for the State Secretariat for Economic Affairs, declined to discuss the findings but said the results were given in late September to Swiss prosecutors.
"Let me say it this way," Wyss said. "If all this information . . . had been false, we would not have passed the results of our preliminary inquiry to the prosecutor."
A spokesman for Switzerland's general prosecutor confirmed Monday that the agency had cooperated with German investigators in the nuclear black market probe but declined to comment further.
In a brief interview in March at his home in the northeastern Swiss village of Haag, Tinner said his family had not been involved in any wrongdoing. He acknowledged working as a mechanic for a Malaysian firm, Scomi Precision Engineering, but said he was unaware of what the company's products were being used for.
The probe into the nuclear network began in October 2003, when a German ship carrying containers bound for Libya was searched in the port of Taranto, Italy. Inside the containers, investigators said they found centrifuge parts manufactured by Scomi that they suspected were intended to help Libya enrich uranium.
Tinner worked as a consultant for Scomi from April 2002 until October 2003 and had a reputation for being secretive, Malaysian officials said.
Upon leaving the company, he erased technical drawings from the firm's computers and took other records, giving "the impression that [he] did not wish to leave any trace of his presence there," according to a Malaysian police report.