South African prosecutors have dropped all charges against a businessman accused of smuggling nuclear-related materials to Libya. They have offered no explanation for the surprise move.

A spokesman for South Africa's chief prosecutor said all charges have been withdrawn against businessman Johan Meyer, but he would not say why or offer any further comment on the matter.

The prosecutor handling the case also had no comment when contacted by VOA. All questions have been referred to the chairman of South Africa's Council for the Non-Proliferation of Weapons of Mass Destruction, who was not taking phone calls. He issued a brief statement saying "investigations are ongoing."

South African authorities last week charged Mr. Meyer with three violations of the Nuclear Energy Act and the Non-Proliferation of Weapons of Mass Destruction Act.

Police searched Mr. Meyer's business last week and seized 11 shipping containers holding what they call components of a centrifuge uranium-enrichment plant.

South African officials say the materials are not themselves a weapon of mass destruction, but they are a key part of the process of developing a nuclear weapon.

U.S. and South African officials have linked Mr. Meyer to Libya's now-abandoned nuclear-weapons program. After his arrest, the U.S. Embassy in Pretoria issued a statement praising South Africa for its efforts in helping break the nuclear proliferation network run by Abdul Qadeer Khan, the father of Pakistan's nuclear bomb.

News that the charges had been dropped came as a surprise, several hours after Mr. Meyer appeared in a courtroom southeast of Johannesburg. His attorneys had unexpectedly withdrawn his bail application, and he was remanded in custody.

Outside the courthouse, Mr. Meyer's lawyer, Heinrich Badenhorst, refused to comment on most aspects of the case, including his client's guilt or innocence, and whether he intended to cooperate with authorities. But the attorney denied allegations that Mr. Meyer has ties to the A.Q. Khan network.

"At this stage of time there is no indication as to any link whatsoever directly between my client and the alleged international network," said Heinrich Badenhorst.

In the past year, at least three others - either South Africans or people with ties to the country - have been arrested on nuclear-related smuggling charges in the United States, Germany, and South Africa.

The International Atomic Energy Agency has sent a team of inspectors to South Africa to monitor the Meyer case.

South Africa's apartheid government secretly built six nuclear bombs before dismantling its nuclear program in 1991.