The alleged assault occurred on Tuesday while the children were on their lunch break in an area of woodland near the school.
The school reported the incident to the council and to the police on Wednesday after the visibly shaken girl told teachers of her ordeal.
“I don’t know if the boys have confessed. The police are investigating the matter now, but we consider this to be a very serious incident,” Thomas Brandin at Linköping council said at press conference held on Tuesday, local newspaper Corren.se reports.
Linköping police have confirmed that the boys have not yet been interviewed and that they have classified the case as rape.
The school has however talked to the boys and confirms that they have admitted the offence, according to a report in the Dagens Nyheter newspaper.
As the boys are under the age of criminal responsibility there will not be a legal consequences as a result of the alleged rape.