Two people were killed and at least seven were hospitalized following stabbings in the Finnish city of Turku, Police have reported.
Police said they have shot a man in the leg after he was suspected of carrying out the stabbing in the western city.
People should stay away from the city center, police said on their Twitter account.
Police also said they reinforced security at Helsinki airport and train stations following the attack.
Prime Minister Juha Sipila said the government was closely monitoring the ongoing police operation and holding an emergency meeting later Friday.
Witness Laura Laine told broadcaster YLE that she stood approximately 20 meters (65 feet) from where the stabbing took place.
"We heard that a young woman was screaming. We saw a man on the square and a knife glittered. He was waving it in the air. I understood that he had stabbed someone," Laine was quoted as saying.
Police planned a news conference at 7 P.M. in Turku, about 150 kilometers (90 miles) west of Helsinki, with Finland's interior minister and the national police chief.
"Police have told us not to go to the city center so we are in this coffee shop a few blocks away from the city center," said Vanessa Deggins, an American who is studying business in one of Turku's three universities. She didn't witness the actual attack, but heard sirens going past.
"This is a safe country by American standards. I have gone home alone at 2-3 A.M. ... I feel safe. This is a safe country."
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