TWO people are dead and several injured after a stabbing in Finland. Police shot one suspect and were investigating initial reports that he may not have acted alone.
At least six people have been hospitalised following the stabbings in the Finnish city of Turku.
"There are eight victims in the stabbing. Two dead and six injured," Turku police tweeted after the assault in a market square.
Three people are now undergoing surgery state broadcaster YLE reports, citing hospital sources.
The attack occurred at two market places close to each other in the city centre - Kauppatori, known in English as Central Market Square, as well as the Puutori Market Square, police said.
"At this stage, there is only one suspect and we are investigating whether there are more people involved ... but it looks likely (he was alone)," said Markus Laine from the National Bureau of Investigation at a news conference. "At this stage, we do not investigate this (as a terrorism attack) but the possibility has not been ruled out."
Police shot the suspect in the leg and he was later taken to hospital. They launched a manhunt for other possible attackers.
"We can not exclude the events being linked to international terrorism," Chief of police Seppo Kolehmainen said. "We have a heightened awareness level of terrorism currently but we did not have any specific threats to act upon."
"There was only one shot fired and the aggressor was apprehended and brought to hospital," he said.
Finland's Interior Minister Paula Risikko said she did not yet know whether the attack was related to terrorism.
"We have not been able to confirm the person's identity ... we have been in contact with the immigration service as the person looks like a foreigner," she said.
In a video purporting to show the aftermath of the attack, screams sound like "Allahu Akbar" - Arabic for "God is the greatest" - however many have argued on social media that the phrase sounds like "beware" in Finnish.
The stabbing spree comes with Europe on high alert a day after drivers slammed vehicles into pedestrians in two attacks in Spain, killing at least 14 people and injuring more than 100 others.
In a separate attack in the German city of Wuppertal-Elberfeld, one man was stabbed to death and another injured.
The Finland attack took place in the heart of the port city in southwestern Finland, just after 3pm (10pm AEST) in a bustling neighbourhood.
"I saw an old woman, I tried to help her. She was bleeding all over her body," Wali Hashi, who witnessed the attack, told AFP.
"She was wounded to her neck with the knife... I took her aside."
Speaking to CNN, Kent Svensson, 44, said "people were running everywhere".
"This guy had this huge knife in his hand - and several times he was stabbing this person," he said. "This guy was just constantly stabbing. He was just turning around, flinging his knife everywhere. There were people lying everywhere."
"We were just talking about what happened in Barcelona," he said. "We thought we were safe in Finland. And then this happens.
"The woman was on the ground. She was dead. It's just awful," he said.
"The government is closely following the events in Turku and the ongoing police operation. The government will meet later today," tweeted Prime Minister Juha Sipila ahead of a cabinet meeting.
Witnesses said they saw a pool of blood following the attack.
South-West Finland police said on Twitter: "Several people stabbed in central Turku. People are requested to avoid the city centre."
Finnish police are reinforcing security at Helsinki Airport and train stations following the Turku stabbings.
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