A couple and their teenaged daughter were found hanging dead in their house in Salem district early on Saturday, the police said.
The incident came to light when the couple's son, who had stayed overnight in his grandmother's house, arrived and knocked at the door of the parents' residence, they added.
Since there was no response, he called up his relatives and they informed the police who broke open the door and found the three hanging.
Investigations are on to find the reason for the death, the officials said.
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