Authorities in Bangladesh have arrested three factory officials in connection with a fire Saturday that killed at least 110 people.

The police chief in the capital, Dhaka, said the officials were arrested Wednesday amid allegations that managers told employees to return to work after fire alarms rang, and that locked doors trapped workers inside.

Hundreds of workers were unable to get out of the Tazreen Fashion factory as the fire burned. Fire officials say a lack of emergency exits contributed to the number of deaths.

Thousands of workers protested for a third day Wednesday, blocking streets and throwing stones at buildings.

Bangladesh has about 4,000 garment factories that make clothes for international brands. The country earns about $20 billion annually from overseas clothing sales, roughly 80 percent of its exports.

Work conditions at the country's garment factories are notoriously poor. Officials say at least 500 people have died in Bangladesh in garment factory accidents and fires since 2006. Activists say plant owners are rarely prosecuted for poor safety conditions.