Campaigning ended on Sunday for by-elections to Asansol Lok Sabha seat and Ballygunge assembly constituency in West Bengal.

Canvassing concluded at 5.30 PM in both the constituencies where voting will begin at 7 AM on April 12 and end at 5 PM, a senior EC official said.

A total of 133 companies of central forces will be deployed in the two constituencies 70 in Ballygunge and the remaining in Asansol while there will also be live webcasting in 100 per cent booths in the assembly constituency and 51 per cent of the booths in the Lok Sabha seat.

A total of 680 of the 2,012 booths in Asansol and all 300 booths in Ballygunge have been designated as "sensitive", he said.

No untoward incident has been reported during the campaigning period from the first week of March and central forces have regularly conducted route marches in sensitive pockets of the two constituencies, the official said.

While 10 candidates are in the fray in Ballygunge and eight in Asansol, the main fight is expected to be between the Trinamool Congress and its principal adversary BJP, while CPI(M) and Congress has also put up its nominees in both the seats.

The by-elections were necessitated as Babul Supriyo resigned as MP of Asansol after joining the TMC from the BJP, while state minister Subrata Mukherjee, who represented Ballygunge, died last year.

The TMC has fielded Bollywood's 'Bihari Babu' Shatrughan Sinha, who was earlier with the BJP, in Asansol, which has a substantial Hindi-speaking population, against Asansol Dakshin MLA of the saffron party, Agnimitra Paul.

Mamata Banerjee's party has fielded Supriyo in Ballygunge where he is pitted against BJP's Keya Ghosh and CPI(M)'s Saira Shah Halim.

Senior BJP leader Ravi Shankar Prasad and Tripura Chief Minister Biplab Deb are among those who have campaigned for Paul in Asansol, while TMC national general secretary and Mamata Banerjee's nephew Abhishek Banerjee has canvassed for party candidates in both the constituencies.