According to the lead investigation, about 28 kilograms of methamphetamine, 14 kilograms of amphetamines and 5 kilograms of cocaine were confiscated during the period.
The preliminary investigation has established that the drugs were en route to Norway, Russia and Japan via the country.
Five people have been detained in connection with the drug trafficking. The suspects are from Baltic countries and Central Europe. However, no Finn is under suspicion.
According to the investigation, the seizures are not linked to each other.
Lead investigator Tero Virtanen described the cocaine and methamphetamine confiscations as considerably huge.
The preliminary investigation is under way and the case and pressing of formal charges could be made in the beginning of the year.
