South African authorities abruptly announced Wednesday that they had dropped criminal charges filed last week against a Pretoria man accused of possessing components used to make bomb-grade uranium for nuclear weapons.

The move was part of a deal in which the man, Johan Andries Muller Meyer, 53, is expected to cooperate with prosecutors in their investigation of other targets, a source familiar with the probe said on condition of anonymity.

Police arrested Meyer last Thursday in Vanderbijlpark, an industrial town 50 miles south of Johannesburg, where he is a director of Trade Fin Engineering. He was charged with violating South Africa's strict laws against nuclear proliferation.

Eleven shipping containers of components for a gas centrifuge, used in the enrichment of uranium, were confiscated in the investigation, along with related documentation and a machine that can be used to make other weapons components, officials said.

The arrest was part of an international investigation into the nuclear black market established by Abdul Qadeer Khan, the architect of Pakistan's nuclear weapons program, who helped Libya and other countries develop weapons programs.

Authorities were cautious in their public statements Wednesday. Sipho Ngwema, spokesman for the Scorpions unit, an agency similar to the FBI, declined to comment on whether Meyer remained under suspicion for wrongdoing, saying only that charges had been dropped.

Meyer's attorney also declined to comment, according to news reports.

-- Craig Timberg

Johan Andries Muller Meyer leaves a court in Vanderbijlpark, South Africa, after officials withdrew charges that he sold uranium enriching equipment.