Four suspected members of the gang were arrested following raids in France on 17 September, said the Europol agency this week.
More than 80 investigators from Bulgaria and France were involved in the raids, following a probe into human trafficking for labour exploitation and money laundering.
Police had identified 167 possible victims working for four wine companies based near to Lyon, said Europol. It did not name any companies involved.
Workers were recruited in Bulgaria via a legally registered employment agency, which offered them €60 per day plus housing and transport for seasonal work in France, said Europol.
‘In reality, they were sent to France in unlicensed transport and then put up on a campsite with money taken out of their wages for meals,’ it said.
Money was also taken out of wages for transport and other charges, it said.
‘The workers’ final salaries were often not enough to even cover their trip back to Bulgaria.
‘The network used this money and laundered it through properties in France,’ said Europol, which helped to co-ordinate the operation between Bulgarian and French forces.
Of those arrested, three were believed to be recruiters from Bulgaria and one was a French national suspected of handling logistics in France.
