Police arrested a man suspected of the stabbing in the city of Turku on Friday. He was shot in the leg before he was taken into custody.
“There are eight victims in the stabbing. Two dead and six injured,” Turku police tweeted.
Security forces tweeted that police were “looking for other possible perpetrators.”
“People are requested to avoid the city center,” South-West Finland police tweeted at 4:40 p.m. local time.
Police warned that several other suspects could still be at large.
Tabloid Ilta-Sanomat said six people were injured, one man and five women, and that a woman with stroller was attacked by a man with a large knife.
Witnesses reported hearing multiple gunshots. The attacker shouted extremist slogans allegedly linking him to the Daesh Takfiri terrorists, they said.
The stabbing spree comes hot on the heels of two deadly car ramming attacks in Catalonia which left 14 people dead and some 100 others injured.