The police on Monday found dismembered body parts of a missing CPI(M) leader, which were buried at two places in Birbhum district.
A couple was arrested in this connection and an extramarital affair could be the reason behind the killing, the police said.
Subhash Chandra Dey, a 58-year-old local leader of the CPI(M), was a resident of Nanoor area of the district while his body parts were discovered near Dubrajpur, around 70 kilometres away.
"Two persons were arrested in connection with the murder. The parts of the body have been recovered. Prima facie, an extramarital affair could be the motive behind the murder," Birbhum Superintendent of Police Shyam Singh said.
However, he said, the police are not ruling out other possibilities behind the killing of Dey who was an insurance agent by profession.
The body parts were found in two gunny sacks buried in the bank of the Ajay river and a nearby agricultural field - both under Dubrajpur police station limits.
After Dey's family members lodged a missing diary, the police started an investigation. His mobile was last traced near Dubrajpur on Friday and the police came to know during the probe that he had visited the house of a couple known to him.
The police sources said when Dey visited the couple's house, only the woman was present and her husband, on reaching home, found them in compromising position.
He allegedly hit Dey with an iron road killing him. Later his body parts were chopped off, hidden in gunny bags and buried, the sources said.
The couple confessed their guilt, they claimed.
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