West Bengal witnessed violence through the day as the state saw a turnout of nearly 80% - lower than 82% in the same seats in 2009 - in the last phase of polling on Monday.
Though no one was killed, four persons were shot at and several others were injured by sharp weapons in Haroa in Basirhat constituency of North 24-Parganas district that adjoins state capital Kolkata.
Almost all 17 constituencies that went to the polls simmered with violence all day, making this phase the most violent of the five phases of polling in Bengal.
Left Front chairperson Biman Bose demanded re-polling in more than 800 booths.
"The fifth phase has been a mockery of democracy. There has been a lot of bloodshed. In many places people were not allowed to exercise their voting rights freely and fairly," he said.
In Amdanga, also in North 24-Parganas, Chandan Das, 27, an activist of the CPI(M)-affiliated Students Federation of India, was pushed into a vessel of boiling oil allegedly by ruling Trinamool Congress activists.
He escaped with burn injuries on his hand but suffered serious head injuries when he was beaten mercilessly after he extricated himself from the vessel.
Those who received bullet injuries alleged that Mrityunjoy Mondal, the husband of the ruling party's Minakha MLA, led a mob of about 35 people who shot at a group of CPI(M) supporters going to a polling booth to vote. The MLA was allegedly present at the spot.
The police arrested more than a dozen people, including the son of a local Trinamool leader for their involvement in the attack.
"Our cadres, supporters, party offices and even general voters came under attack. The ruling party is trying to loot votes because there is a strong anti-Trinamool wind across the state," CPI(M) politburo member Brinda Karat said after casting her vote in South Kolkata.
Reacting to media reports on the violence, state chief minister Mamata Banerjee claimed there was collusion between the media and rich political parties.
"There's hardly any room for doubt that a few major cash-loaded political parties have taken control of media houses and engaged them to serve their narrow political interests, trampling on the ethics of democracy and the voice of the people," Banerjee wrote in a Facebook post.
Said Trinamool general secretary Mukul Roy, "Voting was free and fair. The polls of 2004, 2006 (assembly) and 2009 were full of violence. The media focused on 10 booths out of nearly 31,000 and claimed there was a plethora of violent incidents."
(with PTI inputs)