Last year police and Customs confiscated twice the amount of Subutex, which is often used as a recreational drug, than the year before.

Authorities say the drug's availability has spread throughout the country.

Most of it is brought in by couriers from major European cities, particularly Paris and Amsterdam. They enter Finland most often through the Baltic states, with smaller amounts of the drug coming in through Sweden.

Last year the largest number of those detained on serious drugs charges were Finnish citizens, a total of 712. The second-largest national group was Estonians, with 76 drug suspects, followed by Russians, of whom there were 31. Twenty-one suspects were categorised as stateless, while 13 were from the Netherlands.

"About half of suspects in all customs offences are foreigners," says Esko Hirvonen, a senior official at the National Board of Customs. "This phenomenon is not just restricted to drug trafficking. Most are of course people from nearby areas, but the number of nationalities involved is constantly growing."

New drugs pop up all the time

Officials say that their main concerns at the moment, however, are new designer drugs and counterfeit pharmaceuticals, which are often purchased online from central Europe and Asia.

Last year, Finnish laboratories identified more than 40 new designer drug compounds. Underground manufacturers are able to change drug compositions much faster than authorities can move to ban them.