The incident took place late Monday night near the Adolfbergs school, the local Nerikes Allehanda newspaper reports.
According to police, the group of teens reported how a woman “wearing strange, old clothes” approached them in the playground and prodeeded to pull out a bow and several metal-tipped arrows.
As the youngsters watched in disbelief, the woman then placed an arrow in the bow and fired at them from close range, prompting them to flee the area.
“There was a group of us who ran into her while we were on our bicycles and I saw her walking by. I reacted over the fact that she had a bow under her arm and thought it was strange,” a witness told the newspaper.
Police continue to search for the woman, having received a number of tips during the day on Tuesday.
“I’ve never experienced a case like this and haven’t heard of anything like it either,” police investigator Malin Nilsson told news website Nyheter24.
One theory being considered by investigators is that the mystery archer, described as being between 20- and 40- years-old, may have been involved in some sort of fantasy or roll-playing game.
Speaking to Nerikes Allehanda on Wednesday, Nilsson said she was “hopeful” police would succeed in finding and apprehending the woman following a steady stream of tips from members of the public.