A total of 53 per cent of 3.11 lakh voters exercised their franchise till 5 pm in the by-election to Kurhani assembly seat in Bihar, officials said.
Polling began at 7 am across 320 booths in the constituency, he said.
Tight security arrangements are in place across all the booths, which are manned by central paramilitary forces besides the local police, and the casting of votes will continue till 6 pm.
"Polling has been peaceful, and no untoward incident has been reported so far," the official said.
By-poll to the assembly segment in Muzaffarpur district has been necessitated due to the disqualification of RJD MLA Anil Kumar Sahani.
Altogether 13 candidates, including five Independents, are in the fray.
The main contenders are former MLAs Kedar Gupta and Manoj Singh Kushwaha, fielded by the BJP and Chief Minister Nitish Kumar's JD(U), respectively.
Gupta had lost to Sahani in the 2020 assembly polls by a slender margin of about 700 votes.
The RJD is backing the JD(U) in this by-election.
The counting of votes will take place on Thursday.
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