The assault occurred in the Inner Harbor, at Packhusgatan / Packhusallén, at 2 p.m.
The girl was on her way home from school when the incident occurred.
SVT has been in contact with the girl's mother.
- She was waiting for the bus when the boys approached her and started harassing her.
When she said no, she was punched in the face so she fell, the mother says.
How is she now?
- She is scared, this will be a trauma for her.
She has pain in her nose, neck and headache.
I hope the police get hold of this person who did this.
The police have a report
After the assault, the girl was able to get to Stora torget in Karlstad, where she met a police patrol who then drove her home.
- I do not want to go into whether we have any suspects, says police spokesman Lars Hedelin.
The investigation will be taken over by a department that investigates crimes against children.