The body of an 18-year-old man, whom the BJP claimed as its member, was found hanging from a tree near his home in Purulia district last month.
The incident invited strong criticism of the TMC government from BJP chief Amit Shah, who said the ruling dispensation has "surpassed the violent legacy of the Communist rule" in West Bengal.
An unsigned handwritten note in Bengali found near the body of Trilochan Mahato near his home in Balarampur, about 295 km from Kolkata, stated that he was "punished for working for the BJP" during the recent rural polls in the state, a senior district police officer had said.
In a note to the state government, Social Justice and Empowerment Minister Thaawarchand Gehlot expressed concern over the deaths.
The West Bengal government on Saturday ordered a probe by the criminal investigation department into the deaths.
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