Witnesses to the attack, which took place at Savo Vocational College in Kuopio, 335 kilometres north-east of the capital, Helsinki, said that the man stabbed a young woman in the stomach and released a small bomb in one of the classrooms.
Another witness, Roosa Kokkonen, who works in a garage near the hotel, told Finnish TV channel MTV that a teacher ran out of the building with her hands full of blood.
“While I was helping the teacher, I started to hear more calls for help, and the students ran away into my garage,” Kokkonen said.
Police said that the suspect used a “bladed weapon” during the attack and was also in possession of a firearm. He was shot during the arrest and is being treated at the same hospital in Kuopio.
Finnish Prime Minister Antti Rinne condemned the attack he describes as “shocking” on Twitter.
Police gave no further details on what happened or what provoked the violence. They confirmed that one of the injured was a police officer.
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