Rescue crews carried off the injured and dead on stretchers Wednesday. Some of them used brightly colored material from the garment factories to cart off the victims.
Some onlookers wept while others dug with their bare hands. "After learning that the building collapsed, I rushed here looking for my wife, but until now I haven't found her," said Siraj Miah.
Abdul Alim, a day laborer, said he heard screams from inside the building.
"We couldn't make our way to get in," said Alim, one of thousands of onlookers who tried to reach trapped victims before military, fire and civil defense rescuers arrived.
Flags nationwide were flying at half-staff Thursday after the government declared a national day of mourning.
Workers told to enter
Authorities say they have not determined the cause of the collapse.
Workers from the garment factories said that after the cracks were discovered Tuesday, managers initially ordered them not to report to work the next day.
But factory owners reversed the order, telling employees that the building was safe, said Marjina Begum, who worked on the sixth floor.
Many workers reported to work Wednesday because they were afraid of losing their jobs, she said. More than a dozen other workers corroborated her story.
Managers for the garment manufacturers housed inside the building could not be reached for comment.
M. Atiqul Islam, president of the garment manufacturers association, said owners kept the factories open only after the building's owner told them the cracks did not indicate a threat to the structure of the building.
Employees of a bank branch were removed from the building Tuesday after the crack was detected and were ordered not to show up Wednesday, according to a statement from the bank cited by the news agency. None of the bank's workers was among the injured or dead, it said.
In addition, a strike had shut a mall housing hundreds of shops on the building's two lowest floors.
Links to retailers
Garment contractors here appeal to merchants because of workers' low wages.
It was not immediately clear which retailers were doing business with the factories.
The last major building collapse in the country occurred in 2005 in the same area and killed more than 70 people, the national news agency said.
A fire at the Tazreen Fashions Factory in another suburb of Dhaka in November killed at least 112 people. Tazreen had made goods for Walmart and Sears, though both companies said they were unaware that the factory had made goods for them.
Garments account for 80% of Bangladesh's $24 billion in exports.
The country has about 4,500 garment factories where workers make clothes for various international brands. It's on track to surpass China within seven years as the world's largest apparel manufacturer.
Scott Nova, executive director of the Worker Rights Consortium, said the pressure to cut prices results in substandard safety conditions.
"The worse the dangers get, the more business comes in, so the government has no incentive to fix anything," he said. "We ask ourselves every day what it's going to take to fix this."