Kuala Lumpur, Malaysia ? A businessman who admitted aiding an international black market in nuclear materials was cleared of charges in Malaysia as authorities abroad widened investigations into his alleged role in the sale of atomic secrets to Iran and Libya.

A three-month police investigation found no evidence that Buhary Syed Abu Tahir — or a local company he contracted to make parts for Libya’s nuclear program — broke Malaysian law, national police chief Mohamed Bakri Omar said Saturday.

The government said the finding vindicated its claim that President Bush had unfairly singled out Malaysia in connection to the network, and that the issue should now be put to rest.

Still, Tahir or his associates are the subject of at least two separate investigations overseas, and information he gave police added detail to what is publicly known about the illicit network of Abdul Qadeer Khan.

Khan, the father of Pakistan’s nuclear program, has admitted selling technology and know-how to Iran, Libya and North Korea.

Mohamed Bakri said police have not restricted Tahir’s movement in Malaysia or seized his passport. Tahir, 44, is a Sri Lankan citizen.

“We are not imposing anything on him,” Mohamed Bakri said. “There is no law to bar anybody from leaving this country.”

Swiss police disclosed Friday that they have begun an investigation into whether Urs Tinner, a Swiss engineer named by Tahir as part of Khan’s network, contributed to the production of nuclear weapons.

Tahir is also being investigated by authorities in Kazakhstan, the former Soviet state that served as a nuclear testing ground, where an affiliate of his company may have been dealing in highly enriched uranium, authorities there said.

Tahir told Malaysian police that Khan’s network sold the uranium compound UF6 to Libya and helped it set up an enrichment plant. He also said Khan’s network sold centrifuge parts to Iran in the mid-1990s.

The U.N. International Atomic Energy Agency said last week that Libya had processed a small amount of plutonium and was more advanced in its uranium enrichment program than initially thought.