Immigration officials say that as a rule, people who come to Finland illegally are either victims of human trafficking, or they intend to commit crimes in Finland or elsewhere in Europe.

The Border Guard has five officials working abroad; one in Beijing and four in various places throughout Russia. Their job is to sift through visa applications and flag the ones that seem fraudulent or connected with human trafficking.

"One such case involved a group of very young girls from the easternmost region of Russia," explains Major Ilkka Herrannen. "They were supposedly coming to Finland to compete in a dance competitions for their own local dance groups. But it's extremely unusual that a local event would have to be arranged several thousand kilometres away. So in this case, we decided to advise the Foreign Ministry not to grant these girls visas to Finland."

In addition to pre-emptive measures taken abroad, the Border Guard says it stops hundreds of illegal immigrants at border crossings. South-eastern border checkpoints seize hundreds of forged documents which are used to try and enter Finland.