Police investigating suspected fraud in football have raided properties in three countries, according to officials.
The probe, which ordered a search of the headquarters of the Belgian FA earlier this year, is examining a number of transfers, and Aleksandar Mitrovic’s £13million move to Newcastle United is reported to be part of the investigation.
There have been raids in Belgium, Monaco and London.
Police and tax officials, under the direction of a Belgian anti-corruption judge, detained an agent in Monaco and his assistant in Liege.
News agency AFP report that a judicial source has confirmed to them that Mitrovic’s transfer is part of the investigation.
"The facts involve notably money-laundering operations and private corruption in the context of football player transfers," the prosecutor's office said in a statement.
Mitrovic, signed from Anderlecht by Newcastle, was sold to Fulham last summer after a successful half-season loan at Craven Cottage.