0147 GMT January 19, 2020
Police and security forces said Sunday the clashes broke out in the eastern state, which has been in chaos since Indian Prime Minister Narendra Modi's Bharatiya Janata Party (BJP) won most parliamentary seats last month, Presstv Reported.
"Three of the dead were BJP workers while the other was a Trinamool Party supporter," an unnamed police official told the AFP news agency, adding that at least 18 people were wounded in the clashes.
Both the BJP and Trinamool accused each other of the killings . Local BJP leader Mukul Roy tweeted three BJP workers were "shot dead" in Sandeshkhali in West Bengal.
3 BJP workers shot dead by TMC goons in Sandeshkhali, West Bengal. @mamataofficial is directly responsible for unleashing violence against BJP workers.
West Bengal State Minister Jyotipriyo Mullick, who belongs to the Trinamool Party, said one of the party supporters was "hacked and shot dead by BJP workers.”
"When he was on his way to attend a party meeting, he was hacked at first. When he managed to free himself, he was shot dead," Mullick told reporters in Sandeshkhali.
Sayantan Basu, BJP's general secretary in the state, said in a separate report that the violence had erupted over the hoisting of BJP flags and the putting up of posters.
"They tried to throw away our party flags and posters and when we protested, our workers were shot from point-blank range," Basu was quoted as saying by the Press Trust of India news agency.
Local police have not immediately issued a statement about the conflict.
Rival supporters have regularly clashed in West Bengal where the BJP won 18 seats, up from two in 2014, en route to its massive nationwide win in May.
Last month, a BJP supporter was shot dead in state capital Kolkata and a car belonging to a Trinamool member was pelted with rocks.
Modi's party won 303 seats in the national parliament, increasing its previous tally of 282 seats in 2014.