Police and finance ministry investigators raided 12 locations across the country on Thursday in connection with an investigation into money laundering involving an un-named Islamic organisation, broadcaster NOS reported.
The probe centres on an Islamic organisation which is suspected of laundering hundreds of thousands of euros via educational and other charities, the broadcaster said.
The premises raided included four homes in Brabant, two in Utrecht and one in Zuid-Holland. A mosque in Tilburg and Utrecht and other properties in The Hague and Nieuwegein were also part of the investigation.
NOS says the organisation received large cash payments both in the Netherlands as well as from Saudi Arabia and other Middle Eastern countries. Some of the money was then sent back abroad.
NOS did not say if anyone had been arrested. The investigation focuses on a man and his two sons who have a variety of positions with 10 different foundations.
The public prosecution department has not yet issued a statement on the investigation.