The deceased were identified as Morsheda Begum, 50, Dudu Mia, 60, Hosne Ara Begum, 50, and Farid Mia, 42.
Among them Morsheda Begum and Dudu Mia worked in local brick-kilns. Hosne Ara Begum was an assistant health inspector at Ichhapur Health and Family Welfare Centre in Bijoynagar. The identity of Farid Mia was not confirmed immediately.
All of the deceased were auto-rickshaw passengers.
According to police and locals, a covered van carrying goods was heading towards Sylhet in the morning. When the covered van reached Rampura area, it collided head-on with the auto-rickshaw coming from the opposite direction.
Morsheda Begum and Dudu Mia died on the spot while Hosne Ara Begum and Farid Mia were later taken to hospital in critical condition and died shortly afterwards.
Sarail Khantihata Highway Police Station officer-in-charge Aslam Hossain told Prothom Alo that the bodies were kept in the custody of the police station.
He further said a case is being prepared in this regard. Two vehicles involved in the accident have been seized. However, the driver of the covered van escaped. Police have been trying to catch him.