A Trinamool Congress worker was allegedly stabbed to death in West Bengal's Paschim Medinipur district in the early hours of Thursday, hours before polling started in the area, police said.
Uttam Dolui, 48, was at a local club in Hariharpur in the district's Keshpur area along with a few others when around 10-15 people allegedly attacked him with sharp weapons, they said.
He died on the way to a hospital in Midnapore, they added.
Dolui's family alleged that BJP "goons" attacked him to create tension in the area and intimidate voters ahead of the polling.
The BJP dismissed the allegations, saying they have no reason for resorting to violence as they are confident about winning the Keshpur seat.
The incident triggered tension in the area, which has a history of political violence.
The Election Commission said that a report has been sought from district authorities over the incident.
Forces have been deployed in the locality to check any further flare-up, police said.
Seven people have been arrested in connection with the incident, they said.
A further investigation is underway, police said.
Keshpur is voting in the second phase of the assembly elections with polling starting at 7 am.