While opposition parties have cried foul over transparency concerns, Prime Minister Sheikh Hasina, seeking a third straight term and a record fourth in all, shrugs off the complaints.
Bangladesh's deadly election campaign entered a final full day on Thursday with followers of Prime Minister Sheikh Hasina parading in the streets while her opponents insisted the vote would not be free and fair.
Both sides launched new salvoes in their war of words ahead of Sunday's polling.
Hasina accused the opposition of organising bomb attacks while the Bangladesh Nationalist Party said "the state" was aiding an assault on the opposition.
Flag-waving supporters of the ruling Awami League marched in Dhaka and other cities ahead of the official close of campaigning early Friday. The BNP, whose leader is in jail, said it had been prevented from holding its closing rally.
At least six people - four from the BNP and two from the Awami League - have been killed since the campaign started on November 8.
The BNP and its ally Jamaat-e-Islami say more than 11,500 of their followers have been arrested and thousand of activists, including candidates, injured in attacks by ruling party followers.
Amid international concern over events, UN Secretary General Antonio Guterres appealed for calm.
Guterres "calls on all stakeholders to ensure an environment free of violence, intimidation and coercion before, during and after the elections, so as to enable a peaceful, credible and inclusive poll," said a spokesman.
Bangladeshis "must feel safe and confident in exercising their right to vote. Civil society and electoral observers should be fully supported to play their role in the process," the UN leader added through his spokesman.
The United States called off an observer mission it was financing because of delays issuing visas.
Sheikh Hasina, seeking a third straight term and a record fourth in all, has shrugged off opposition complaints of authoritarianism and said she needs more time to implement her ambitious economic plans.
Amid a flurry of late campaign appearances on Wednesday, Hasina said the "BNP-Jamaat alliance carried out bomb attacks in 88 constituencies".
"There is no doubt that the people will surely reject them," she said.
Hasina focused a speech broadcast by video late on Wednesday to supporters in Dhaka on the impressive economic growth of the past decade.
She has promised to increase annual growth to 9.0 percent from the current 7.8 percent, expand electricity coverage and put the country on course to raise average incomes to more than $5,400 by 2030.
Hasina slammed the opposition for failing to recognise Bangladesh's achievements. "They are blind despite having eyes," she said.
"I call upon people to continue the pace of improvement and give us more scope to serve again."
The Awami League leader won a landslide victory in 2008 and the BNP boycotted the 2014 election - saying it was not free and fair - gifting her a return to power.
But since her last victory, civil society and rights groups have accused Hasina's government of silencing dissent and muzzling the press.
BNP leader Khaleda Zia, a political arch-rival of the prime minister, was jailed for 17 years this year on graft charges.
"The election process has turned into a farce," BNP spokesman Fakhrul Islam Alamgir said. "All the attacks are made on BNP people."
"It is very unfortunate and unimaginable that these attacks are being sponsored by the state itself," he added, according to the Daily Star.
The BNP-led opposition alliance has accused police of siding with the Awami League and said they were barred from holding a final rally on Thursday.
Opposition parties sought permission to hold a rally in Dhaka's Suhrawardy Udyan grounds, an alliance spokesman Latfiul Bari Hamim told AFP.
"We made the application on December 22 but two days later police said they could not give us permission," Hamim said.
Dhaka police said they were not aware that permission had been sought.