By Roland Buerk
BBC News, Dhaka
Police and security forces have been deployed to protect garment factories in industrial areas of Bangladesh.
Bangladesh garment makers fear the violence will mean lower exports
The operation has prevented a repeat of widespread rioting which destroyed or damaged dozens of factories on Saturday, Monday and Tuesday.
But many owners kept their businesses closed for fear of more attacks. Only about a quarter of the factories in the capital, Dhaka, were operating.
Unions say garment workers are angry over low pay and long hours.
Wages in Bangladesh's garment factories can be as little as $20 a month.
All through the working day, the police, the paramilitary Bangladesh Rifles and the Rapid Action Battalion were deployed in heavy numbers around garment factories.
The garment industry, which brings in 80% of Bangladesh's exports, has been hit badly by three days of rioting in a week.
What began as a dispute over dismissals in a single factory quickly spread to engulf industrial areas. On Tuesday, 14 factories were set alight, according to the fire brigade, and many more were damaged.
Factory owners and the government have suggested a conspiracy may be behind the violence.
Some owners have claimed that agents from rival garment-producing countries might be stirring up discontent.
Bangladesh's industry has grown by about 20% since a quota system that regulated the world's garment trade was phased out at the start of 2005.