Police have fired tear gas and used batons to disperse stone-throwing protesters amid a second day of violence in the Bangladeshi capital.
A number of people were injured and several arrests were made in Dhaka as a three-day nationwide transport blockade called by opposition parties continued.
The Awami League and its allies want elections set for this month postponed, saying they will not be free and fair.
Bangladeshi President Iajuddin Ahmed says the elections will go ahead.
Checkpoints
The BBC's John Sudworth in Dhaka says police fired tear gas to clear the area around the presidential office in the centre of the capital.
But he says the violence so far is not on the scale of Sunday, when dozens were reported injured in a number of outbreaks of rioting across the city.
Much of the transport system remained paralysed on Monday and most businesses were shut, witnesses said.
Opposition activists manned checkpoints to prevent vehicles moving.
President Ahmed says the elections will go ahead as planned on 22 January.
He has headed a caretaker government since the ruling Bangladesh Nationalist Party (BNP) handed over interim power at the end of October.
Late on Sunday, a presidential adviser said the interim administration would consult the opposition to try to end the impasse.
Previous agitation over the issue has led to more than 30 deaths countrywide and the opposition parties say the protests will continue until their demands are met.
The Awami League said more than 1,000 activists were detained ahead of the protests.
Its main demand is that the government use an updated version of the 2000 voter register, and not one created over the past few years.
The political bloc led by the BNP accuses the Awami League of "sensing defeat" and being determined to sabotage the elections.
Photo caption
Protesters in Dhaka, Bangladesh