Bangladesh garment factories reopened Wednesday as hundreds of thousands of workers returned to key manufacturing hubs after days of violent protests demanding a near-tripling of the minimum wage.

The South Asian country has been rocked by the worst labour unrest in a decade, with tens of thousands of workers clashing with police for a 23,000 taka ($208) minimum monthly wage, up from the 8,300 taka set by the government five years ago.

Bangladesh's 3,500 garment factories account for around 85 percent of its $55 billion in annual exports, supplying many of the world's top brands including Levi's, Zara and H&M.

But conditions are dire for many of the sector's four million workers who have been hard hit by soaring prices of food, house rents and costs of education and healthcare.

Rights groups have said that many workers are half-starving.

A government-appointed panel raised the sector's wage last week by 56.25 percent to 12,500 taka, but garment workers have rejected the hike, sparking further protests with at least 70 factories ransacked.

But top union leader Babul Akhter said on Wednesday that while they still rejected the 12,500 taka minimum wage, he urged the workers to return to factories.

"We've not budged from our demand for 23,000 minimum wage," Akhter told AFP.

"We have also asked the government to release all detained workers and scrap the charges against 23,000 workers."

Police said scores of factories, which were shut down due to the protests at the main trouble-spots of Ashulia and Gazipur last week, reopened after the manufacturers held talks with the workers over the past two days.

"Hundreds of thousands of workers entered the factories," Sarwar Alam, the head of Ashulia industrial police unit, told AFP.

"There is no violence. All factories are open."

Violence triggered by the wage protests left at least four workers dead, including three who were shot by police. Nearly 140 workers and around half a dozen union organisers were arrested over the clashes, according to police.

At least 10,000 unidentified garment workers were also charged with violence as part of the crackdown, police said.

Bangladesh Prime Minister Sheikh Hasina last week rejected any more wage hikes and warned that the protests could cost jobs.

Some of her key ministers and dozens lawmakers of her ruling Awami League party are powerful garment manufacturers.