The traders were returning to their neighbourhood after buying vegetables from the wholesale market in Manikganj’s Jaagir.
The incident took place inside the project area around 10:30am on Tuesday, said Ruhul Kuddus Tutul, senior administrative officer of the project.
The workers were injured when the rods tilted after the collapse, he said.
Sheikh Md Nasir Uddin, OC of Ishwardi Police Station, said he heard about the incident, but had not been officially informed.