The boys were arrested on Monday and taken in for questioning over the incident.
“A preliminary investigation into aggravated child rape has been launched,” prosecutor Mikael Karlsson told the Expressen newspaper.
Karlsson refused to confirm how many boys were suspected for taking part in the rape, which is believed to have occured in a Stockholm suburb in late February or early March.
He also refrained from divulging the ages of the suspects beyond saying that several were younger than 15-years-old, the age of criminal responsibility in Sweden.
“I can’t say how many people have been questioned. All who have asked for legal representation are younger than 15,” Karlsson told the paper.
According to Expressen, the boys are believed to have filmed the incident.
The recording has since been obtained by police and constitutes the bulk of the evidence gathered against the boys.
Because the matter involves a sex crime with both suspects and a victim under the age of 15, few details have yet to emerge about the case.
According to Expressen, a similar incident took place in 2010 in which a 14-year-old girl was raped by five young perpetrators who also filmed the attack.
The boys were sentenced to youth community service and court ordered care after being convicted of aggravated rape and sexual molestation.