Assembly elections began in India's most populous state of Uttar Pradesh on Thursday, with Prime Minister Narendra Modi's Bharatiya Janata Party seeking a second term. More than 150 million people are eligible to vote in the state of 220m. The seven-stage election is being held over the next four weeks and results will be declared on March 10. Voting began at 7am amid tight security in 58 of the state's 403 assembly constituencies, including Agra — the city of the Taj Mahal. Election authorities said turnout was at 20 per cent by afternoon amid several reports of glitches in electronic voting machines. The incumbent chief minister Yogi Adityanath, a Hindu monk and politician, campaigned on his governments's infrastructure development in the state. His main challenger, former chief minister Akhilesh Yadav of the Samajwadi Party, accuses the BJP, a right-wing Hindu nationalist party, of using sectarian politics to win votes. The election in the bellwether state is being seen as a referendum on Mr Modi's leadership before the next general election due in 2024. Mr Modi hand-picked Mr Yogi to lead the Uttar Pradesh government after the BJP won a large majority in the 2017 state election. The prime minister and other top BJP leaders have been campaigning in the state. The second round of polling will be held on February 14. Four other states — Goa, Uttarakhand, Manipur and Punjab — will also vote over the next four weeks to elect new state assemblies.