The arrestees were identified as driver Md Selim, 60, of Amanatpur village in Begumganj upazila and his associate Abu Zafar, 35, of Barishal district.
Mamunur Rashid, officer-in-charge of Sadar Dakshin Police Station, said the locals rescued the girl and handed over the culprits the police after giving a mass thrashing.
Eyewitness Mazharul Alam, a student of Comilla University, said he and some of his friends were waiting for a bus in the area and they heard screaming of a girl from a parked bus on the opposite side of the road.
“We rushed there and found the girl’s hands tied with a piece of rope while the driver and his two of associates were inside the bus,” he said.
One associate, however, managed to flee from the scene, he added.
The girl was kept at the child care unit of Sadar Dakshin Police Station, said Sub-inspector (investigation) Tomal Krishna Dhar of the police station.