France seized around 140,000 "illegal" masks during a police operation near Paris on Saturday.
Two men were arrested in the afternoon whilst unloading "several boxes" from a cargo coming from the Netherlands in the suburban area of Saint-Denis, about 10 kilometres from the capital.
Authorities opened an investigation on "possession of counterfeit goods and deceptive marketing practices", the Bobigny prosecutor's office said.
The case is now entrusted to territorial security.
The two men arrested were aged 60 and 46.
One of them presented himself as a "business owner", explaining having bought the masks, of which around 5,000 are FFP2, in the Netherlands, for a total value of €80,000, police said.
They were being stored in a building in a residential area in Saint-Denis.
The goal was to resell them to "acquaintances", like workers in the construction industry, and make "big profits", according to the French police.
This is the largest seizure of protective masks since the government’s ban on their resale.
In March, 32,500 masks from China were seized from a warehouse in Saint-Ouen, and 28,800 masks were discovered in a shop in the wholesalers' district of Aubervilliers.
In both cases, the loads recovered by the police were handed over to the Regional Health Agency (ARS).