Polling for the Bankipur assembly by-election in Bihar began at 7 am on Thursday amid tight security arrangements, officials were quoted as saying by news agency PTI

Around 3.80 lakh voters are eligible to exercise their franchise to decide the fate of 26 candidates, including Jan Suraaj Party founder Prashant Kishor, who is making his electoral debut.

Voting will continue till 6 pm, a senior official at the office of the state Chief Electoral Officer said. Counting of votes is scheduled for August 3.

BJP national president Nitin Nabin vacated the seat after he was elected to the Rajya Sabha in April.

Nabin had won the assembly seat for the fifth consecutive time in November last year, defeating his nearest rival Rekha Gupta of the RJD by over 50,000 votes.

The BJP has fielded youth wing leader Neeraj Kumar Sinha.

The saffron party has not lost the seat since 1995, when the constituency was known as Patna West.

According to Election Commission data, all 422 polling booths in the constituency are located in urban areas.

Talking to reporters outside the state capital's Jakkanpur police station, Kishor said, “I have been camping here for the past few hours, and the police is unable to divulge whereabouts of more than 16 of my supporters who have been rounded up.”

"I am not describing these as arrests since there is no record of which of my people have been named in which case. I came to this police station after learning that they had been kept at the Jakkanpur police station. But, here I am told that they have all been taken to different police stations. The SHO here even claims that the police station was not involved in the detentions, which were carried out at the instance of higher-ups," the former poll strategist alleged.

Police officials were, however, not immediately available for comments on Kishor's allegations.

The Jan Suraaj Party founder claimed that "clearly, the ruling BJP is behind these detentions".

Voting is also being held for bypolls in Madhya Pradesh's Datia and Gujarat's Manjalpur today.

(With agency inputs)