“Police shot the suspected perpetrator in the legs,” police wrote on Twitter. “The person has been arrested. We recommend that people avoid central Turku.”
Police did not confirm the number of victims.
Public television station Yle reported that central Turku was on lockdown, with witnesses saying they had seen bodies lying on the ground in a busy area of the town. Businesses were shut.
“The government is following the situation in Turku closely and a police operation is under way,” tweeted Prime Minister Juha Sippila ahead of a cabinet meeting.
MTV3 television reported that police have raised security at Helsinki airport and at train stations.
In 2012, Finland’s then-prime minister Jyrki Katainen escaped a knife attack in Turku while campaigning for municipal elections.
The man who approached him carrying a knife was found to be psychologically disturbed and no charges were brought against him.