A grocer was shot dead in front of his wife by unidentified men in West Bengal's Nadia district, the police said on Saturday.
Haralal Debnath, 52, was shot dead at Habibpur on Friday night, a police officer said.
BJP MP Jagannath Sarkar said Mr Debnath was a party worker, and alleged the ruling Trinamool Congress was behind the killing. The TMC denied the allegation.
"We were preparing to close our shop. Two persons came posing as customers and asked for some goods. When my husband turned to give them those goods, they fired at him and fled," Mr Debnath's wife Chandana Debnath said.
After the men opened fire, she said she shouted for help and soon people came running to the shop. They took her husband to Ranaghat Hospital, 84 km from Kolkata, where he died.
"We are investigating the matter," senior police officer VSR Ananthnag said.
Nadia South BJP chief Manabendra Nath Roy said, "He was our booth-level worker and served the BJP since 1995. The TMC had threatened him earlier. Now they killed him."
Local TMC leaders said the party has no connection to the killing.