Three judicial magistrates have also been appointed to oversee polling between 2 and 6 September.
As many as 21 executive magistrates are also on poll duty to maintain law and order. Some 17-18 members of law enforcement agencies, including police and Ansar, are manning each polling booth.
Meanwhile, mobile forces, comprising police, APBn, Ansar, 12 striking forces, 12 teams of RAB and 12 platoons of Border Guards Bangladesh (BGB), have been deployed to ensure peaceful voting.
The constituency fell vacant after its MP Mahmud Us Samad Chowdhury succumbed to Covid on 11 March.
The by-poll was deferred twice due to a surge in Covid-19 cases.
On 26 July, the High Court stayed the by-poll to the constituency till 5 August due to the worsening Covid situation in the country. Later, the court asked the election commission to complete the by-poll by 7 September.
Habibur Rahman Habib got the AL ticket for contesting while the other candidates -- Mohammad Atiqur Rahman of Jatiya Party, Junaid Mohammad Mia of Bangladesh Congress and Shafi Ahmed Chowdhury -- are in the fray as independents.
Some 350,000 people are eligible to vote in the by-poll.