(CNN)The offices of top Portuguese soccer teams SL Benfica, FC Porto and Sporting CP were raided by Portuguese authorities on Wednesday, as part of a massive anti-corruption probe.
Cristiano Ronaldo's agent Jorge Mendes one of many embroiled in widespread anti-corruption probe
The offices of superstar agent Jorge Mendes -- who represents players including Cristiano Ronaldo -- were among a number of locations searched according to several reports in Portuguese media.
The Portuguese Prosecutor General's office says it has established 47 entities -- both collective and individual (including soccer players, agents, lawyers and club officials) -- and placed them under official investigation on suspicion of fraud and money laundering.
In a statement, the Portuguese Prosecutor General's office confirmed 300 officials, including more than 100 tax inspectors, 180 police and more than a dozen magistrates were involved in 76 raids across the country.
As part of what authorities called "Operation Offside" investigators are looking into transfers completed since 2015, which are suspected of "activities destined to evade paying taxation due to the state.".
In separate statements, SL Benfica, FC Porto and Sporting Lisbon all confirmed they are cooperating with investigators.
Other Portuguese teams such as Sporting de Braga and Vitória de Guimarães have also confirmed their offices were raided.
Mendes' soccer management company Gestifute, which represents Portuguese soccer star Ronaldo, declined to comment.
Super agent Mendes has represented a number of other high profile figures in the sport, including Tottenham Hotspur manager Jose Mourinho and Manchester United goalkeeper David de Gea.
The lawyer for Mendes, Ronaldo and Gestifute -- Carlos Osorio de Castro -- was also targeted in the investigation, according to his office, which confirmed searches at the premises, but declined to provide additional details.
Retired Spanish goalkeeper Iker Casillas confirmed investigators were also at his house and said he was working with authorities.
"Transparency is one of my principles," he wrote on Twitter.
In a statement to CNN, the Portuguese Prosecutor General's Office said it was unable to provide further details as to which homes and premises had been searched or who had been established as formal suspects, given that the investigation is still ongoing.