Manchester City have been reported to FIFA by Velez Sarsfield over the alleged "trafficking" of a youngster they signed.
City signed Benjamin Garre from Velez in July after he turned 16, beating off competition from Manchester United and Barcelona.
However, according to Argentine side Velez, City tried to sign Garre while he was 15 -- a move they claim breached FIFA's rules on the transfer of minors. FIFA has strict rules in place to help prevent clubs signing players under the age of 18 from outside the European Union to prevent the exploitation of minors.
"Never have I experienced such an immoral act," Velez president Raul Gamez is quoted as saying by the Daily Telegraph.
"They offered money to take a 15-year-old child who is in the middle of his stage of development. We don't know what they offered the father and the child in order to convince them."
City have, according to the Daily Telegraph, denied any wrongdoing as they claim Garre holds an Italian passport, which would have entitled him to join the club on his 16th birthday.
City also reportedly say that FIFA has approved the transfer, though the governing body has yet to comment on the deal.
The Daily Telegraph, however, adds that Velez are confident FIFA will punish City in the same way as they have Barcelona, Real Madrid and Atletico Madrid in recent years for violating its rules on the transfer of minors.
In a statement outlining their "trafficking" allegation, Velez claim City offered to pay them €50,000 when Garre made his professional debut, followed by further payments of up to €1.05m depending on subsequent appearances.
Velez say they rejected the offer as it was contrary "to good faith, confraternity, solidarity and respect for the regulations applicable to football, characteristic of any club with renowned performance and prestige as is in this case Manchester," only for City to then make an application to FIFA to allow them to sign Garre on the basis that he held an Italian passport.
Gamez, speaking to Argentina's Gol de Vestuario, linked the exodus of several of Velez's youth players, including Garre, to the current problems in the Argentina FA.
"We had a youth player stolen from us. While AFA keeps messing around, we will continue to be without protection," he said.
In June, FIFA appointed a committee to run the federation's daily affairs, with a stipulation that elections must be held by July 2017.
Velez also previously released a statement in June saying they were against the idea of Garre leaving the club, while warning City that the signing would breach FIFA rules.
"In Velez, we defend values and we act in good faith," Gamez added. "We are not interested in collecting €50,000 or €1 million if said action is prohibited and may affect the player.
"What is most important in these cases is the formation and development of the child, in a supportive environment, above economic or strictly sports interests. It is crazy to think that our youngsters can find themselves in a situation of vulnerability or abuse in a foreign country, without their family or somebody to protect them."
Gamez added that Velez will take their complaint to the Court of Arbitration for Sport if they have to.