According to an official of the Nandanvan Police Station, the incident occurred at around 1.30 am in the city's Aradhna Nagar area.
"According to preliminary investigations, they were attacked and killed by some sharp weapons as they slept. There were no signs of struggle or robbery. The bodies have been sent for autopsy," the official said.
The victims have been identified as Kamlakar Pavankar, 45, his wife Archana, 40, their daughter Vedanti, 12, a nephew Ganesh Palatkar, four and grandmother Mirabai, 70.
The police will investigate all angles, including business rivalry, they said.
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