Nine polling officials have been withdrawn from their election duties in the Thakurgaon-1 by-election following allegations that they directly or indirectly supported the ruling party.

The officials were replaced after the allegations surfaced, District Election Officer and Returning Officer Kamrul Islam told reporters on Wednesday night.

The withdrawn officials included teachers from different educational institutions and a bank official.

They are Masud Rana, assistant presiding officer at Sabuj Government Primary School polling centre in Thakurgaon municipality; Zainal Abedin of Thakurgaon Government College polling centre; Julfikar Ali of Thakurgaon Road Girls' High School polling centre; and Farida Yasmin of Gopalpur Government Primary School polling centre.

The others are Sadekul Islam of Salandar Panchpir Danga Ebtedayi Madrasa polling centre; Mohammad Ali Jinnah of Singia Munshipara Government Primary School polling centre; Obaidur Rahman of Daulatpur Soleman Khan Multipurpose High School polling centre; Shahadul Islam of Balapara Dimukhi High School polling centre; and Abdul Jabbar of Baragram Alim Madrasa polling centre.

All nine were serving as assistant presiding officers.

According to the election office, the Thakurgaon-1 constituency, covering Thakurgaon Sadar, Ruhia and Bhulli, has 185 polling centres — 113 in Thakurgaon Sadar upazila, 33 in the newly formed Ruhia upazila and 39 in Bhulli upazila.

The constituency has 516,138 registered voters, including 250,053 men, 256,572 women and four third-gender voters.

A total of 287 voters have registered to cast their ballots through postal voting, including 249 men and 38 women.

Voting is scheduled to take place from 8am to 4pm on Thursday without any break. Authorities have emphasised preparations at individual polling centres and security arrangements to ensure voters can exercise their franchise without obstruction.

Five candidates are contesting the by-election.