An Austrian manufacturer of FFP2 facemasks is being investigated for allegedly selling Chinese masks under the label "Made in Austria".
Federal prosecutors say the company, which has not been named, is suspected of "organised illicit work and serious commercial fraud".
"FFP2 masks produced abroad were allegedly repackaged ... and sold as masks produced in Austria at a higher price," the public prosecutor said in a statement.
"The repackaging of the FFP2 masks was carried out by persons without the required registration for social security."
The investigation has been launched against "a known person" and those responsible for the manufacturing company.
According to the Austrian Press Agency, the masks in question are of Chinese origin.
Senior prosecutors have also conducted two searches at separate sites belonging to the company.
"The amount of damage is still being investigated," the statement continued.
"In view of the ongoing investigations, it is not possible to provide further information on the accused persons or associations, or on individual further investigative measures."
In January, Austria was one of the world's first countries to make FFP2 masks compulsory in shops, schools, and on public transport in light of the COVID pandemic.
Health Minister Rudolf Anschober confirmed last month that FFP2 masks would also be required in some outdoor areas.
Opposition parties have criticised the government for a "lack of appropriate tendering procedures" for the mass production of the masks in Austria.