Police in Austria have carried out nationwide raids over the suspected sale of fake vaccination passes.
In total, 22 people are under investigation for "forgery, use of falsified documents and fraud", the interior ministry said in a statement.
The searches come just a few weeks before Austria becomes one of the first EU countries to make COVID-19 vaccines mandatory. On Wednesday, Italy announced it was making them obligatory for the over 50s.
Officials say the suspects are all anti-vaccine activists who are accused of trafficking fake health certificates for themselves and their families.
"The suspects form a heterogeneous group, with the only common factor being the rejection of public protection standards," the interior ministry said on Wednesday.
A number of fake vaccine passes -- as well as mobile phones and computers -- were seized as part of the operation.
The investigation was launched after police officers infiltrated a group on the messaging platform Telegram.
"This is not a minor offence, but a criminal act," said interior minister Gerhard Karner, adding that he would take action "especially against counterfeiters and those who do business in the shadows".
Austria had set up a dedicated police group to combat the sale of fake vaccine certificates in April 2021.
According to official figures, around 70% of Austria's population has been fully vaccinated against the virus, and amid a rise in Omicron cases officials are pushing forward with a vaccine mandate.
From February, unvaccinated citizens will in theory only be allowed to leave homes for food shopping, sporting activity, or medical treatment.