The case was registered on Monday on the directions of senior police officers, SHO Parbhakar Kentura said.
Earlier, police has registered a suicide case.
According to a complaint lodged by the woman, the four accused - Sarvan, Amit, Afsar and one unknown person - forcefully entered her house in Atali village in Budhana on June 6 and strangled her husband to death and raped her. The accused later hanged her husband's body from a tree.
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