Colombian pop superstar Shakira has reportedly been accused of tax evasion and could even face a prison sentence.
Spanish tax authorities say she owes income tax for 2011-2014, arguing that she was resident in Spain then.
They have asked Spanish prosecutors to open a tax evasion case against the singer, whose fortune is reckoned to be more than $200m (£176m), according to the BBC.
The tax bill could be tens of millions of euros, Spanish media report.
Sources close to Shakira, who became a full tax resident in Spain in 2015, told La Vanguardia she had always met her tax obligations and was ready to abide by the 'economic consequences' of what they considered could be simple differences in 'evaluation criteria' rather than a deliberate attempt to evade taxes.
Shakira has not yet publicly addressed the tax evasion reports.
The global superstar - also famous for philanthropic work - is the partner of FC Barcelona footballer Gerard Piqué.
The tax officials are seeking four years of unpaid taxes from all her global income - not just income generated in Spain.
Spain's Efe news agency said Shakira's auditors, PriceWaterhouseCoopers, had confirmed the tax investigation.
People who spend more than six months a year in Spain are considered residents for tax purposes.
In recent years Spain has seen several high-profile court cases involving football stars accused of tax-dodging.
Last May a 21-month jail term was confirmed for Barcelona and Argentina footballer Lionel Messi.
However, Spanish law allows terms of under two years to be treated as probation, and Messi is still playing.
