Mohammad Maeen Uddin, officer in charge of Trishal police station, said when the microbus was heading towards Dhaka from Dhobaura upazila around 2:00am it overturned and caught fire.
On information, a team of firefighters went to the spot and doused the fire, said Abul Kalam, station officer of Trishal Fire Service Station.
"They recovered four charred bodies from inside the microbus. The deceased included two women," he said.