Thousands of Bangladeshi garment workers barricaded roads in Dhaka Wednesday demanding fair wages for clothing they make for major Western brands, with at least two killed during days of protests.

Sabina Begum, a 22-year-old seamstress, said she joined the protests because she was "struggling to ensure bread and butter" for her family, saying the monthly minimum wage of 8,300 taka ($75) did not cover basic needs.

"How can we spend a month with 8,300 taka when we need to spend 5,000-6,000 taka alone for the rent of a one-bedroom house?" Begum told AFP.

The garment worker protests come as Bangladesh also reels from separate anti-government demonstrations, with opposition party supporters demanding Prime Minister Sheikh Hasina step down ahead of elections due by the end of January.

Bangladesh's 3,500 garment factories account for some 85 percent of the South Asian country's $55 billion exports, but conditions are dire for many of its four million apparel workers.

Major Western companies including Adidas, Gap, H&M and Levi Strauss purchase goods from Bangladesh manufacturers.

Bangladesh's powerful manufacturers' association has offered workers a 25 percent pay raise, ignoring demands for a nearly threefold increase to the basic salary.

Police said at least 5,000 garment workers, demanding a monthly minimum wage of 23,000 taka ($208), set up roadblocks in the capital Dhaka.

An AFP correspondent at the protests said the number of workers could be significantly higher.

Assistant Commissioner of Dhaka Metropolitan Police Omar Faruq said no violence had been reported on Wednesday in the city.

However, a crowd of some 1,500 protesters hurled rocks at multiple factories in the industrial city of Gazipur, regional head of the industrial police unit Sarwar Alam told AFP.

"We fired tear gas and sound grenades to disperse the protesters," he said.

- 'Hunger and injustice' -

Garment worker Nurul Islam, 25, accused supporters of the ruling party of attacking the protesters. "We want justice, we want a sufficient wage," Islam said.

Police could not confirm any such attack but the Prothom Alo newspaper quoted witnesses reporting that a ruling party activist had fired a gun.

"The ruling party men attacked our people yesterday," Islam said. "The owners don't want to raise our wages. Should we die of hunger and injustice?"

Protests began early last week but violence escalated on Monday when tens of thousands left their shifts and staged protests in Gazipur, where a six-storey factory was torched by workers, leading to the death of one labourer.

Another worker was killed during clashes between police and protesters.

On Sunday, police charged opposition Bangladesh Nationalist Party (BNP) leader Mirza Fakhrul Islam Alamgir and more than 150 other top party members with the murder of a policeman during the anti-government demonstrations.

The violence has sparked international concern, with seven nations including the United States, Australia, Britain, Canada and Japan urging all sides to "exercise restraint, eschew violence and work together" for a free and fair vote.

The country of nearly 170 million people has overtaken neighbouring India in per capita income, with the garment industry at the centre of its impressive growth over the past two decades.

Hasina's government set up a panel this year to set a new minimum wage.

Unions say that garment factory owners -- who include ministers and influential lawmakers -- have played a role in fixing the minimum wage during past negotiations.

Faruque Hassan, the president of the Bangladesh Garment Manufacturers and Exporters Association (BGMEA), said Tuesday they would raise minimum wages from next month but without specifying by how much.