She Zhijiang had been in Thai custody since 2022 after spending more than a decade on the run from Chinese authorities, accused of ties to the Myanmar gambling and fraud hub Shwe Kokko.

A Thai appeals court upheld China's extradition request this week for the 43-year-old, who also holds Cambodian nationality, after lengthy legal wrangling.

He was flown out of Bangkok's Suvarnabhumi Airport around 4:30 pm (0930 GMT), the police official said.

The businessman was escorted from the airport's police station with his hands braced behind his back by armed and masked Thai police, an uncommon practice for local officers.

An Interpol red notice published in May 2021 and obtained by AFP said She faced criminal charges in China related to running online gambling and fraud operations.

She and his company Yatai have already been hit with sanctions by Britain and the United States.

Washington says he transformed a village on the Myanmar-Thai border into Shwe Kokko -- "a resort city custom built for gambling, drug trafficking, prostitution, and scams targeting people around the world".

The gleaming city is one of the most infamous of the hubs thriving in Myanmar's border regions, which have devolved into hives of black market activity since a civil war consumed the country in 2021.

The hubs gained international notoriety for housing internet fraud factories where workers -- some of them trafficked -- rob foreigners with romance and business cons worth billions of dollars annually.

In pleas written from a Bangkok prison and seen by AFP, She denied all allegations of criminality and insisted his company was simply an "urban developer".

His attorney Daniel Arshack has told AFP the allegations against She were "fabricated" and, once in China, "it is expected that he will be deprived of due process, tortured, and ultimately disappeared".

She's Thai lawyer Sunya Eadjongdee declined to comment on Wednesday, saying the extradition was a confidential matter.

Scam victims in Southeast and East Asia alone were conned out of up to $37 billion in 2023, according to a UN report, which said global losses were likely "much larger".

Beijing has led an international pressure campaign to crack down on the scam hubs, irked at its citizens being lured to work in the industry and targeting other Chinese with their cons.

China sentenced five people to death this month for their involvement in a violent criminal gang with fraud operations in Myanmar's Kokang region.