There were no immediate reports of any poll-related injuries in West Bengal
India's battleground state of West Bengal took the centre stage in the fourth phase of a staggered general election on Monday after clashes broke out between supporters of Prime Minister Narendra Modi's party and a regional bloc.
In West Bengal, a populous eastern state where Modi is trying to gain seats to offset likely losses in northern India, security forces chased away people wielding sticks after workers from Modi's Hindu nationalist Bharatiya Janata Party (BJP) took on those from regional Trinamool Congress, police said.
An official with the Election Commission of India said paramilitary forces fired a blank round inside a polling station in another constituency in the state after a scuffle between voters and troops, who were demanding that mobile phones be kept aside while voting, as rules state.
There were no immediate reports of any poll-related injuries in West Bengal, where at least one person was killed and three injured during the third phase of voting last week.
The election, the world's biggest democratic exercise with about 900 million voters, started on April 11 with Modi in the lead amid heightened tension with long-time rival Pakistan.
The last phase of voting is on May 19. There are a total of 545 seats in parliament's lower house.
The BJP is in a direct, and sometimes bloody, fight in West Bengal with Trinamool, whose chief, Mamata Banerjee, is one of Modi's biggest critics and a possible prime ministerial candidate.
The BJP holds only two of West Bengal's 42 parliamentary seats.
"We have asked for central forces at all polling booths so that free and fair elections can be held in the state," said Mukhtar Abbas Naqvi, a minister in Modi's cabinet, referring to federal paramilitary police.
Modi told a rally in West Bengal that at least 40 Trinamool state lawmakers were in touch with him and would leave the party after votes are counted on May 23.
Trinamool accused Modi of attempting to horse-trade, telling him: "Nobody will go with you."
The party also alleged that federal security forces were trying to influence voters to back the BJP wherever they were deployed.
Maidul Islam, a professor of political science at Kolkata's Centre for Studies in Social Sciences, said the stakes were high for both parties with Trinamool hoping to be part of a federal government coalition.
In disputed Jammu and Kashmir state's Anantnag constituency, which is voting in three phases due to security concerns, paramilitary forces fired teargas and pellets to disperse youth throwing stones at them, a police officer said.
Four persons suffered pellet injuries, of which two had been hospitalised in Srinagar, the summer capital of Kashmir, the officer said, declining to be identified since he was not authorised to speak to the media.
More than 128 million people are eligible to vote in this round of the seven-phase election held across 72 seats in nine states. The election commission said about half of them had voted by mid-afternoon.
Modi's coalition won more than 75% of the seats in the nine states in the previous election, in 2014.
Many of the constituencies are in Uttar Pradesh state in the north and western India's Maharashtra, where the financial capital Mumbai is located. Uttar Pradesh elects the most lawmakers, with Maharashtra next and West Bengal third. The two former states are ruled by the BJP and its allies.
However, political analysts say the BJP may struggle to repeat its strong showing this time due mainly to a jobs shortage and weak farm prices, issues upon which the main opposition Congress party has seized.
First-time voter Ankita Bhavke, a college student in Mumbai, said she voted for economic development.
"I want the country to be at par with the best in the world," she said. "There's been some progress in the last five years."
India's financial markets were closed on Monday for the election.
Modi has played up his record on national security after he sent warplanes into Pakistan in late February in response to a suicide bomb attack by an Islamist militant group based there that killed 40 Indian police in the disputed Kashmir region.
In recent days, he has evoked the deadly Easter Sunday bombings in neighbouring Sri Lanka to remind voters of the dangers India faces.