The national flag flew at half-staff in government buildings. The country's factories were closed as a mark of respect, and prayers for the dead were held in places of worship across the Muslim-majority South Asian nation.
Relatives and colleagues gathered near the site of Saturday's blaze, many wearing black badges as a sign of mourning.
"I've lost my son and the only member to earn for the family," said Nilufar Khatoon, the mother of a worker who died. "What shall I do now?"
Some labor organizations planned rallies later on Tuesday. About 15,000 workers protested on Monday blocks away from the gutted factory, blocking traffic on a major highway in a suburb of Dhaka, the capital.
In a statement issued on Tuesday the European Union deplored the loss of lives in the fire and urged the Bangladesh government to improve working conditions in garment factories.
"The European Union has always been very clear about the need to improve working standards and safety in this sector," said the statement. European market is a major export destination of Bangladesh textiles.
The fire was the deadliest of many to hit garment factories in Bangladesh in recent years. The industry has grown from nothing to become the country's dominant exporter in little more than three decades, but factories often ignore safety in the rush to supply major retailers in the U.S. and Europe. More than 300 people have died over the past six years in Bangladesh garment-factory fires.
Wal-Mart said on Monday that the factory, owned by Tazreen Fashions Ltd., had been making clothes for the U.S. retail giant without its knowledge. Tazreen was given a "high risk" safety rating after a May 2011 audit conducted by an "ethical sourcing" assessor for Wal-Mart, according to a document posted on the website of Tazreen's parent company, the Tuba Group.
Wal-Mart said the factory was no longer authorized to produce merchandise for Wal-Mart but that a supplier subcontracted work to it "in direct violation of our policies." The retailer said it stopped doing business with the supplier on Monday.
"The fact that this occurred is extremely troubling to us, and we will continue to work across the apparel industry to improve fire safety education and training in Bangladesh," Wal-Mart said in a statement.
Survivors of the weekend fire said an exit door was locked, fire extinguishers didn't work and apparently were there just to impress inspectors, and that when the fire alarm went off, bosses told workers to return to their sewing machines. Victims were trapped or jumped to their deaths from the eight-story building, which had no emergency exits.
Maj. Mohammad Mahbub, fire department operations director, said investigators suspect a short circuit caused the fire. But he added that if the building had had even one emergency exit, "the casualties would have been much lower."
The Bangladesh Garment Manufacturers and Exporters Association, which has offered $1,250 to each of the families of the dead, urged investigators not to rule out sabotage.
"Local and international conspirators are trying to destroy our garment industry," association President Shafiul Islam Mohiuddin said. He provided no details.
Investigator Mainuddin Sarkar said the government is "looking into all possibilities, including sabotage."
Police said on Tuesday they were questioning a woman accused of trying to set fire to another factory in the area on Sunday. Local police chief Habibur Rahman said police also arrested a man who the woman says paid her to set the fire, and that police were investigating whether the two are linked at all to the Tazreen fire.
Bangladesh has some 4,000 garment factories. The country earns about $20 billion a year from exports of garments, mainly to the U.S. and Europe.