A government minister says the death toll in a factory building collapse in Bangladesh has reached 161 as rescue workers continue to hunt for more survivors and victims.

The junior minister for Home Affairs, Shamsul Haque, says that by late Thursday morning a total of 2,000 people had been rescued from the wreckage of the building.

Wednesday's accident has reignited questions about the often lethal conditions in the country's garment industry.

The disaster in the Dhaka suburb of Savar came less than five months after a factory fire killed 112 people and underscored the unsafe conditions faced by Bangladesh's garment workers, who produce clothes for global brands worn around the world.