A Civil Guard statement today said officers seized two Leifeld metalworking machines that had been imported illegally from Britain last year.
The statement said the machines are classified as "dual use" meaning they can be used in both civilian and military industry and their shipping to Iran would violate UN sanctions.
It said three Spaniards and one Iranian were arrested in the cities of Barcelona, Tarragona and Palma de Mallorca. They were charged with membership of a criminal gang, trafficking dual-use goods and money laundering.