According to the source, the youngsters would come to Portugal with the promise that they would play in certain clubs, but in the end they only had the opportunity to "show" themselves in training.
Those who pleased stayed, the others would be "abandoned to their fate."
The suspect also got payments from some players in exchange for false promises of contracts.
A 47-year-old from Angola, the suspect was arrested on Thursday and is indicted for crimes of aiding illegal immigration, qualified fraud and forgery of documents.
According to the SEF source, the suspect would use "forged" documents on behalf of some clubs, especially in the districts of Braga and Porto, to facilitate the entry of young people into Portugal.
These are mainly young people between the ages of 18 and 21, but there will also be some younger ones.
The investigation has been ongoing since 2020, and on Thursday two search warrants were carried out, one at home and the other at a company.
"Documentation was seized that could corroborate the evidence already in the process", says a statement from the SEF.
The suspect was presented to the Criminal Investigation Court of Guimarães, which applied the coercive measures of weekly periodic presentations at a police station, ban on leaving national territory with delivery of a passport to the court and ban on contacts with other suspects.
The court also fixed the delivery of 5000 euros, as a bond.
The operation was carried out by eleven SEF inspectors.
According to a source from the SEF, the investigation will continue.
