Former Brazil star Ronaldinho Gaúcho and his brother are to remain in pre-trial detention in Paraguay after allegedly trying to enter the South American country using false passports.

Ronaldinho and Roberto Assis, who had travelled to Paraguay on Wednesday to attend a charity event, appeared in court in the capital of Asunción on Saturday, and could be held for up to six months.

They were arrested on Friday, despite a prosecutor who believed they were tricked into taking the fake documents recommending they be released after receiving an alternative punishment, such as paying a fine to charity.

Ronaldinho

• Gallos Blancos
• Midfielder
• Brazil

• News
• Stats

Ronaldinho and brother a flight risk, Paraguayan judge says

"This is a serious, punishable offence because he has threatened the interests of the Republic of Paraguay," the judge Clara Ruiz told reporters.

Explaining the court's refusal to release the pair into interim house arrest, Ruiz said: "There is a flight risk, he has no roots in the country, he entered illegally and is here illegally. That's why the court has decided that he must remain in custody."

Lawyer says "stupid" star didn't realise documents were fake

Speaking to the Brazilian newspaper Folha de São Paulo, Ronaldinho's lawyer, Adolfo Marín, said: "He didn't know he was committing a crime, because he didn't understand he'd been given false documents; he's stupid.

"[But] the court doesn't believe this [version of events]."