The deceased, identified as Julie (11), Priti (12) and Mamata (12) took ill after consuming pesticide and were taken to a hospital where they died during treatment, the sources said.
The girls, natives of Mesra village and Class VI students of a secondary school, purchased the pesticide from a shop and consumed it, they said, adding the motive behind this was under investigation.
The shopkeeper who sold the pesticide to the girls was absconding, the sources added.