Barcelona striker Ronaldinho and the former Brazil national football team underwent an investigation by the authorities in Paraguay after his arrival in the country, and the police indicated that it was a fake passport.

In a statement, Ronaldinho, his brother and his agent, Roberto de Assis, were interrogated in their room in a hotel on the outskirts of the capital Asuncion on Wednesday, and then the authorities summoned them on Thursday for further investigations.

Paraguay's Attorney General Federico Delfino explained during a press conference today, Thursday, that Ronaldinho and his brother left an airport in Sao Paulo with two Brazilian passports, then they received two passports belonging to Paraguay once the plane landed.

"Ronaldinho and his brother said that they consider my passport as a gift," Delfino added, noting that preliminary investigations indicate that the numbers in the passports belong to two other people.

The Prosecutor's Office, which cooperates with the police in the investigation, stated that the phones and passports of Ronaldinho and his brother were confiscated.

The two brothers received an invitation to travel to Paraguay from the owner of a nightclub, and Ronaldinho arrived on Wednesday to participate in a children's event and to launch a book.

Ronaldinho, 39, finished his career in 2015 and was the best player in the world at the height of his career early this century.

FIFA chose him the best player in the world in 2004 and 2005, and won the World Cup with Brazil in 2002 and the Champions League with Barcelona in 2006.