Tens of thousands of garment workers have been subdued by police in Bangladesh.

Tear gas and rubber bullets were used by authorities to disperse the crowds who had gathered to demand higher salaries at a rally just outside of Dhaka.

At the Ashulia industrial area, around 30km north of the capital, workers walked off the job and ransacked several factories in support of protesters campaigning against a three-fold wage hike. Local police Chief Sirajul Islam said police were pelted with rocks and live rounds by the protestors, who blocked the highway out of the area for two hours. Chief Islam confirmed that police used rubber bullets, tear gas shells and water cannons to disperse what were termed ‘unruly workers’, prompting a return of fire which left one officer injured.

Forty police officers were wounded in the fighting, which lasted for three hours, according to Islam. He did not make any statement on how many of the garment workers were hurt in the protest, although the left-wing Garment Workers Unity Forum claimed that more than 100 were injured.

Islam told reporters that around 50,000 garment workers were involved in the protest, which is calling for a minimum monthly wage of 5,000 taka (£48). Currently, workers are paid the minimum wage set down by the 2006 manufacturers, unions and the government agreement of 1,662 taka (£16)

The violence follows a string of labour disputes at the two main apparel hubs of Ashulia and Kanchpur, which produce garments for leading global retailers such as Tesco, H&M and Wal-Mart.

One of the world’s leading retailers is forecasting a run on products in its international stores should those countries make the World Cup play-offs.

Wal-Mart operates in eight of the 32 nations that have made it to the FIFA World Cup 2010 in South Africa, and is bracing itself for a boom if the national football team is successful.

Rick Bendel, the international chief marketing officer for Wal-Mart, said that revenue at outlets which had been in operation for a minimum of 12 months before the finals could anticipate a growth of between two and four per cent – with an additional one to two per cent expected if the national team makes the semi-finals.

Bendel said the tournament was a huge television event, and products associated with television such as TV sets, couches, food, drinks and memorabilia would all expect to sell heavily over the tournament. Bendel also suggested that in the UK Asda, which operates under the parentage of Wal-Mart, could benefit from extra revenue in the hundreds of millions of pounds.

FIFA have signed an exclusive agreement for World Cup merchandise with Wal-Mart through a subsidiary, leaving the retailer in the prime position of being able to capitalise on sales of items such as official footballs, beer mugs and plates.

Wal-Mart has stores in 14 countries outside of its US home, with Brazil, Argentina, Japan and Mexico all featuring at the World Cup, while the English team is sponsored by rival supermarket giant Tesco.