The accident happened just after half past seven on Wednesday evening, in the Ljustadalen area.
Police were dispatched to the scene, but it is still unclear what happened.
- We don't know, and we will investigate that, says press spokesperson Marie Andersson.
The police have no information about the condition of the children, who are under 15 years old, but also no information that says it should be serious.
Region Västernorrland states that a child suffered minor injuries and has had to leave the hospital.
Mild damage can correspond to, for example, a finger fracture.
- No one has been informed of any suspicion of crime at the moment, says Marie Andersson at 9.45pm.