BNP-backed candidates, including the chairman aspirant, in Comilla on Saturday boycotted Daudkandi upazila elections alleging vote rigging.
The boycott was announced at a press briefing arranged at the house of Hazi Abul Hashem Sarker, the chairman candidate fielded by the BNP.
Hashem's Chief Election Agent, Masum Reza, said the returning officer had been informed of electoral fraud such as fake voting and capture of polling stations but no action was taken.
He demanded that the elections be cancelled before holding fresh polls.
BNP-backed vice-chairman candidate Shah Alam and woman vice-chairman aspirant Farida Yasmin also announced election boycott separately.
Some 40-45 ballots which had been stuffed were found at Hasanpur Government Primary School centre but the presiding officer, Abdul Matin, said that voters might have left those on the table.
The number of registered voters in the upazila is 239,754.
Six candidates contested for the post of chairman and another 6 for that of woman vice-chairman while 13 ran for vice-chairman.
On April 28, the BNP boycotted city corporation polls in Dhaka and Chittagong alleging massive electoral fraud.