The stabbing happened in Tampere, Finland's third-largest city, which is 180 kilometres northwest of the capital Helsinki.
An assailant in Finland stabbed several people near a shopping centre in the southern city of Tempere on Thursday afternoon, Finnish public broadcaster Yle reported.
It was not immediately clear how many people were injured in the attack, but police said the situation no longer posed a danger to others.
Victims were given first aid at the scene.
Yle said that one person was detained, without giving further details.
Video by Yle showed a heavy police presence and ambulances in front of the cordoned-off mall.
Daily paper Aamulehti reported that police blocked all doors of the Ratine shopping mall and people were not allowed to enter or leave.
Witnesses of the attack were taken to the second floor of the mall for questioning.
Yle also reported that employees from the social and crisis emergency services had arrived at the mall to attend to victims and bystanders.