Ashrafi Devi (60) was assaulted with stick and later killed by her daughter-in-law Neetu (25), her father Kharpattu Yadav and his friend Ramesh Yadav while she was sleeping inside her house in Tala village yesterday, they said.
Police said that Neetu husband's had died four years ago and she was having an illicit affair with her brother-in- law.
As Ashrafi was objecting to their relationship, Neetu planned to kill her, they said.
Police said that an FIR had been lodged and all the accused have been arrested.
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