Lucknow, Voting began on a brisk note Saturday in the Uttar Pradesh bypolls to the 11 assembly and one parliamentary seat.

While balloting was slow owing to a drizzle in the Lucknow (East) constituency, long lines of voters were seen outside polling stations in Charkhari, Sirathu, Balha, Rohania, Nighasan, Saharanpur city, Bijnore, Thakurdwara, Noida, and Hamirpur. Voting is being held under tight security in Mainpuri, the lone Lok Sabha constituency that went to polls Saturday.

Mainpuri with 1,647,176 voters is crucial for the Samajwadi Party (SP) as the seat has been held by the party for over two decades.

Voting in the biggest assembly segment in terms of voters in the bypolls - Noida (523,762) and the smallest Thakurdwara (329,438) - was also under way peacefully.

For the Samajwadi Party, the polls are an opportunity to make a comeback, after its disastrous showing in the Lok Sabha battle where its numbers dipped from 22 to five.

The Mainpuri Lok Sabha constituency was vacated by Samajwadi Party chief Mulayam Singh Yadav. The SP has fielded Tej Pratap Singh Yadav, a grandnephew of Mulayam Singh, while the BJP has fielded Prem Singh Shakya.

The Bahujan Samaj Party has this time decided not to contest. Election officials said adequate arrangements have been made to ensure free and fair elections. "So far polling has been peaceful and we want more and more voters to come out and cast their votes," UP's Chief Electoral Officer Umesh Sinha said. In all, 3,820 micro-observers have been deployed across the 5,939 polling booths of which 1,920 have been declared sensitive.

SP general secretary Ram Gopal Yadav voted in Mainpuri and claimed victory. Talking to reporters, Ram Gopal Yadav said SP's candidates will win handsomely this time as the reality of "false dreams" sold by Prime Minister Narendra Modi during the Lok Sabha polls has been exposed.

"People know what the truth behind Modi's dreams was and they have made up their mind in favour of the Samajwadi Party," he added. Barring Mainpuri which was won by SP chief Mulayam Singh Yadav, all 11 assembly seats were held by the BJP and its ally Apna Dal.