All three people died within a month under suspicious circumstances, police said.
A man was arrested in Rajasthan's Churu district for allegedly murdering his two sons and his grandmother after suspecting that they were not his children, police said on Tuesday.
The man had allegedly killed his sons -- Garvit (4) and Anurag (8) -- February 13 and his elderly grandmother on January 31 by poisoning them in Bhainsli village, Churu Superintendent of Police Jai Yadav said.
To avoid suspicion, Bhup Singh (32) first killed his grandmother and later his children, police said.
According to the SP's statement, police interrogation revealed that Bhup Singh suspected that Garvit and Anurag were not his children. So, he had planned to murder them, it said.
All three people died within a month under suspicious circumstances, police said.
A case was registered in connection with the three suspicious deaths and police started the investigation.
Police exhumed the buried body of deceased child, Garvit, and carried out the post-mortem and the viscera was preserved in forensic science laboratory for testing.
Police said Garvit's viscera report found traces of drugs, which led to Bhup Singh's arrest.
During investigation, police found that Bhup Singh had a medical shop and he had also done a course in nursing, they said.
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