A victim and the suspected gunman were killed, and the motivation was not immediately clear.
Police sealed off the Puuppola area in Jyvaskyla, a town in central Finland, as the investigation was going on.
Further information, including the victim and the suspected perpetrator's age and gender, will be given on Friday, YLE said on its website, posting a picture of two masked policemen.
Alert emerged immediately after midday when gunshots were heard in the Puuppola area.
No one else was reported to have been hurt as some 250 pupils in a nearby school were prevented from leaving when the shooting took place, said YLE.
Finland, considered a peaceful nordic country, has been haunted by shootings generated by personal grievances.
A man shot dead his wife and then killed himself in Helsinki mid June this year. Reports said the couple had a fierce quarrel before the killing occurred.