The three arrested are Jamal Hossain, 30, son of late Badsha Miah of Belumia Char area of Bhola district, and Mohammad Jalil, Manik, 24, son of Abdul Jalil of Charpata area under Daulatpur police station and Monir Hossain, 20, son of Nurul Islam from the Veduria area.
The 21-year-old gang-rape victim was identified as a garment worker, police said.
Confirming their arrest Additional Deputy Commissioner (Port Zone) of the Chattogram Metropolitan Police Alok Biswas said they had been arrested on the basis of a case filed by the victim.
He said three youths raped the victim while she was returning home from work last Friday night. After the incident, the girl came to the police station and lodged a complaint. Three people were later arrested in the raid.
During the primary interrogation, the three arrested persons confessed to raping the girl.
A case has been filed at Bandar police station in this regard, police added.
Another garment worker was raped in the Custom Bridge area the same night.