French charity Foot Solidaire claims that it receives 20 reports a week of hopeful teenage footballers whose parents have paid thousands to give them a start in European club football.
The teenagers are brought to Europe by the gangs, but instead of being greeted with youth contracts at professional clubs they are abandoned onto the streets as soon as they arrive.
African families are usually charged around $2,000 for the young player - generally aged between 14 and 16 - to be sent to Europe, with a promise of a trial awaiting them.
Those families do all they can to give their sons a chance of starting a better life in a new country, often selling homes or businesses to pay the bogus agents.
Once the teenagers arrive in Europe, however, the agents usually pocket the money and flee, abandoning the hopeful stars with no money, no home and no way of contacting their families back home.
Those are the lucky ones, however: in some cases the young men are sold into slavery for a huge fee, with a Sky Sports News report on Monday showing a FIFA-accredited agent offering to sell 14- and 15-year-olds for £25,000.
Even those who do actually land contracts are not immune: last year FIFA warned that unscrupulous agents were scouting at tournaments for future stars who would then subsequently be pressured into taking part in match fixing.