However, the Cenei farm, where the outbreak occurred and has killed more than 7,000 pigs in recent weeks, was not one of them, he said.
"Out of 25 Smithfield farms in Timis county, five do not have sanitary-veterinary authorisation and have been illegally populated with pigs," said Ioan Jeleriu.
Five other unauthorised farms were counted in the neighbouring county of Arad.
Jeleriu had said Sunday that the Cenei farm had been cordoned off. Some 20,000 pigs were to be slaughtered in the coming days in response to the outbreak.