Prosecutors hoping to extend R. Kelly's jail time have urged the judge considering a possible release to keep the R&B star locked up indefinitely, because they fear he's a flight risk.

The singer's lawyer has asked lawmakers to let his client await upcoming trial dates at home, claiming the star's health is deteriorating behind bars.

In papers filed last week, Kelly's legal team explained the singer is struggling with anxiety and an untreated hernia, among other health issues, and they assured the judge he is not a flight risk, because he rarely leaves the U.S. and doesn't currently have access to a passport.

But prosecutors insist Kelly, who was denied bail in July (19) when federal prosecutors from New York and Chicago indicted him on 18 charges, including child sexual exploitation, child pornography production, kidnapping, forced labour, racketeering, and obstruction of justice, cannot be trusted.

According to new legal documents filed by federal lawyers and obtained by TMZ, the singer remains very much a flight risk.

They claim he attempted to travel to Dubai after he was released on bail in Illinois earlier this year.

The prosecution team also fear Kelly will tamper with or intimidate witnesses, explaining he has "a history of coercing women to write letters containing false and embarrassing allegations" so he can later use them as blackmail.

The judge has yet to rule on the I Believe I Can Fly singer's future behind bars.

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