Flags have been flying at half-mast across Finland after a boy was killed and two girls seriously wounded in a shooting at a school on Tuesday.
The shooting took place in a classroom at Viertola school in Vantaa, to the north of the capital, Helsinki.
According to Police said all three victims were 12 and that a suspect, also aged 12, had fled after the shooting but was later detained.
One of the wounded girls has dual Finnish-Kosovan nationality.
All public buildings lowered their flags from 08:00 to 5:00 GMT, on Wednesday to mark a day of mourning, the interior ministry said.
According to Finnish TV channel MTV Uutiset, the boy wore a mask and noise-cancelling headphones while carrying out the shooting.
He ran off as soon as police arrived and was eventually detained “in a calm manner” in the northern Siltamaki district of Helsinki.
Police have opened a murder investigation and attempted murder. In a statement, they said both wounded girls were still in hospital but gave no details of their condition.
They said they were looking into a possible motive but would not yet be releasing details. Public broadcaster YLE reported that the boy had been the victim of bullying.
“There is a lot of different, and partly incorrect, information about what happened in the different channels of social media. The police still want to remind you that spreading incorrect information on social media is a crime,” the police statement said.
Viertola school has 800 students aged seven to 16 of both primary and middle school age on two separate sites, with some 90 staff.
The school was open on Wednesday, but Katri Kalske, the deputy mayor of Vantaa, said that it would close earlier than usual.
She told the AFP news agency that, extensive support has been offered to pupils and staff, and that the shooting would be discussed in all schools in the city in an “age-appropriate manner”.
BBC/Taiwo Akinola