Belgian giants Anderlecht and the country's football association have been raided by police in connection with a money-laundering investigation involving agents and player transfers.
A spokesman for the federal prosecutor said it was not linked to the 2018 probe into match-fixing and fraud.
The Belgian FA told Reuters that police had taken away documents relating to transfers from its headquarters.
Anderlecht said they were cooperating with the investigation.
The prosecutor's spokesman added: "We had some questions for the agents who took care of the transfers. It is a question of money laundering."
Anderlecht are Belgium's most successful football club, having won 34 league titles, the Uefa Cup and two Cup Winners' Cups. However, they have recently endured a difficult period having been fined and docked points when crowd trouble forced a match at arch-rivals Standard Liege to be abandoned.
They are fifth in the Belgian top flight, and could miss out on qualifying for European competition next season for the first time in 55 years.