TBILISI: Georgia on Tuesday announced the arrest of the former top aide to the country's richest man and ruling party founder, as his lawyers warned he risked torture after being forcibly returned.

Giorgi Bachiashvili used to be the right-hand man to Bidzina Ivanishvili, the billionaire founder of the Georgian Dream ruling party, who is widely believed to be the de facto ruler of the mountainous Caucasus nation.

Bachiashvili, who once headed the tycoon's Co-Investment Fund, fled Georgia in early March amid mounting legal troubles.

He has called his former boss Ivanishvili a “power-drunk criminal” who “is trading away the future of our country.”

Sentenced in absentia to 11 years in prison for alleged embezzlement and money laundering, he has accused Ivanishvili of threatening to “crush” him in prison.

On Tuesday, Georgia's State Security Service said Bachiashvili “a dual Georgian-Russian national, wanted on an Interpol Red Notice, was arrested on Monday after an anonymous tip placed him near the neutral zone” at the border with Azerbaijan.

But Bachiashvili’s lawyers claimed that he was “forcibly returned” to Georgia under murky circumstances and now faces an “imminent risk of torture.”

His lawyer, Robert Amsterdam, condemned the arrest, accusing Georgian authorities of misusing international legal mechanisms to target political opponents.

The dramatic arrest comes amid renewed scrutiny of Ivanishvili's influence in Georgian politics and business.

Georgia has been rocked by protests since Ivanishvili's Georgian Dream party claimed victory in October parliamentary elections rejected as rigged by the pro-Western opposition, then shelved talks on joining the European Union.

Critics also accuse the government of sliding into authoritarianism and tilting the former Soviet republic back towards Russian influence -- an allegation it denies.