Union Minister Nisith Pramanik visited the victim's residence to meet the grief-stricken family.
Amid the violence in the run up to the July 8 panchayat polls in West Bengal, the body of a BJP candidate's brother-in-law was found in Cooch Behar district.
Sambhu Das, aged around 30 years, was called outside his home by unidentified youths on Saturday night, police said. Hours later his body with stab wounds was found near a pond.
Union Minister of State (Home) Nisith Pramanik, who visited the residence of Mr Das to meet the grief-stricken family, told reporters on Sunday that the youth was murdered by attackers sheltered by the Trinamool Congress and police and the ruling party supporters were cooking up "stories of love and extramarital affairs whenever an incident happened to deflect attention."
Claiming that everyone's security was at stake in Trinamool's regime, Mr Pramanik said, "There had been attacks even on my life by TMC goons in the past as policemen, who have become stooges of the ruling party, watched silently."
Demanding an impartial probe into the death of Mr Das, Mr Pramanik said, "Whenever poll dates are announced in West Bengal, opposition party activists and their family members are killed by members and supporters of the ruling party."
BJP leader Ajoy Roy had earlier alleged that Mr Das, who had seconded the name of Bisakha Das as a BJP gram panchayat candidate from Dasgram area in Dinhata, was murdered by Trinamool supporters.
Denying Mr Roy's claim, West Bengal minister and Trinamool's Dinhata MLA Udayan Guha said the party had no role in the incident and Mr Das was not a political activist.
"Das was killed due to a personal feud. The BJP gives a political twist to every crime in West Bengal and links it with the panchayat polls," he told reporters.
Referring to Mr Pramanik's allegations, Mr Guha said, "He has been instigating BJP workers in Cooch Behar to resort to violence. Pramanik is responsible for many incidents in the district and north Bengal in recent times."
"Why is Pramanik scared of his security when he moves around with bodyguards of central security forces," Mr Guha, the North Bengal development minister, asked.
BJP state president Sukanta Majumdar warned of "far reaching dangerous consequences" if hooligans sheltered by the Trinamool are not reined in.
In Malda district, Trinamool candidate Mustafa Sheikh was fatally attacked in Sujapur area on Saturday, police said. He was taken to a hospital where he was declared dead, police added.
According to state minister Sabina Yeasmin, former Trinamool activists who had joined the Congress after being denied tickets, were behind the attack on Mr Sheikh.
Widespread violence over the filing of nominations for the three-tier panchayat polls has left at least seven people dead and several injured in various parts of the state.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)