The projects include diplomatic buildings, procurements for the railway, and highway development
The accident took place on the Dhaka-Tangail Highway in the Etahata area of the town around 10:15 early on Sunday, said Mokter Hossain, chief of Basan Police Station.
Police could not immediately confirm the identities of the victims but said they appeared to be between 18 to 20 years old.
"Two of them died on the spot while another person died on the way to Shaheed Tajuddin Ahmad Medical College & Hospital in Gazipur."
Police seized the bus and detained its driver along with his assistant, Mokter said.