Of the 33 persons, 15 persons - 13 Croatian nationals, one Macedonian and one Serbian national - are in custody at the Zagreb County Court investigating centre. The police have issued warrants for the arrest of six persons - both Croatians and foreign nationals, who remain at large.
The arrests are the result of an operation carried out by Croatian police forces in cooperation with the Office for the Suppression of Corruption and Organised Crime (USKOK) and the Slovene and Bosnian police forces and judiciary.
During the operation, 36 apartments, houses and other facilities used by members of the organised criminal gang were searched.
Since July 2006, the gang smuggled at least 300 illegal migrants across the state border, unlawfully obtaining at least one million kuna (approx. 135,000 euros).
The press conference was also attended by senior officials of the Slovene police and the Bosnian border service.
Benko said that French police had thanked Croatian police for cooperation in an investigation into 21 people, including one from the former Yugoslavia, involved in the smuggling of a large quantity of weapons (belonging to the former Yugoslav army) in Marseille.