The girls belonging to three families, were kept in one house by their parents, who had fled from the village following some personal rivalry, Additional Superintendent of Police (Gaya) Ashok Kumar said.
A villager Shambhu Singh had lodged a complaint with the police against the three families over some personal dispute, Kumar said.
The ASP said taking advantage of the situation, unidentified criminals barged into the house and shot dead the five girls, aged between 8 to 13, in their sleep.
Police is waiting for the arrival of the parents of the girls for further action.
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