The men worked for logistics companies and were allowed to operate around the aircraft, the British newspaper The Daily Telegraph reported.
Authorities said they are also searching for ingots, which were taken from the plane just before it left Paris' Charles de Gaulle airport for Zurich, Switzerland.
The 100-pound ingots had been placed inside the plane by Brink's security employees.
Brink's often transports gold to Swiss banks as fund transfers, the Telegraph said.
The company's employees had placed nine suitcases on the plane, but when the aircraft arrived in Zurich, two of the cases were missing.
The security company has denied any responsibility for the missing gold bars.
The incident comes as Air France deals with the seizure of 1.3 tons of cocaine that was aboard one of the airline's flights.
An assistant manager with the airline was among those arrested.
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