The letters campaign by the Finnish army has ostensibly been carried out to "keep in touch" with its reservists, the Finnish Defense Ministry said on its website, and reservists have been asked to update their personal details that the army holds for them.
The letters have been sent as a result of "an extensive reform starting in 2008 affected the task of many reservists and the Defense Forces contacted the reservists to inform them what their individual role would be should Finland enter a conflict," the military's website noted.
The timing of the letters that has raised eyebrows, however, as relations between Russia and its neighbor Finland sour.