Folk beliefs record at least 14 demons into which the soul of the deceased person could be transformed after suffering a bad death.
Among the Drawsko skeletons, the teenage girl is the most probable candidate to have died such a death.
"It is possible that she drowned, committed suicide, was murdered or died another kind of violent and untimely death," the researchers said.
They believe the 50-60-year-old woman that was buried with a sickle on her hips was also considered demonic.
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"The presence of a sickle on her hips, the coin in her toothless mouth and the stone on her neck indicate that she was thought to have demonic features as well," Polcyn and Gajda said.
The other sickle burials belong to people who died in the prime of life. According to the researchers, they were likely considered strangers, non-farmers or religious dissenters.
"We are unable to say which of the criteria of strangeness is indicated here: one or perhaps all three of them," they said.
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Certainly they were not foreigners or migrants. A study led by Lesley Gregoricka from University of South Alabama tested molars from 60 individuals, including those buried with sickles, using radiogenic strontium isotopes from archaeological dental enamel.
The tests revealed these people lived their whole life either in Drawsko or in the nearby villages.
"It is now for archaeological science, particularly biomolecular analyses, to narrow down the question of what lay behind the decision to bury the dead in Drawsko with sickles," Polcyn and Gajda concluded.
According to Elena Dellù, an archaeo-anthropologist at the Catholic University of the Sacred Heart in Milan, these individuals were likely seen in a very negative way as they stood out from the norm.
"They did not conform to social rules, suffered from inexplicable diseases or were seen as demonically possessed," Dellù told Discovery News.
"Those who did not reach certain 'stages,' such as stillborn children, individuals who died just before their wedding, or women who died in labor, were also candidates for deviant burials," she added.
Dellù, who is investigating in Italy two deviant burials of teenage girls, believes the sickle, coin and stone package points to a community strongly fearing the dead.
"Coins were placed in the mouth to favor the deceased's passage into the afterlife. The sickle and the stone would have prevent the dead from returning," Dellù said.