Police shot a knifeman and were searching for other suspects after six people were stabbed in the western Finland city of Turku.
The knifeman injured five women and a man with a knife before he was shot in the leg and detained. The victims included a woman pushing a pram, according to local media reports.
The motive for the attack was not immediately clear.
Police were checking trains and buses out of Turku for other potential suspects.
Mobile phone footage taken from a residential block near to the scene of the stabbing showed a few people running away down the street.
The Finnish broadcaster YLE said several people were seen lying on the ground in Puutori Square in central Turku. Police used Twitter to urge people to avoid that part of the city.
Prime Minister Juha Sipila said the government was monitoring the ongoing police operation and holding an emergency meeting later Friday.