While his 12-year-old son's body was found hanging from a bathroom window, bodies of his wife and younger son were found lying in a bed in the bedroom.
Their relative, a differently abled boy, was with them when the alleged incident occurred in the early hours today, but he was not aware about it, police said.
They said Nisha's parents, who were staying there, had left for their hometown in Idukki district at 4 am.
Police suspect that financial crisis could have been the reason for Sinoj to take the extreme step.
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