17-year-old Md Israfil and 15-year-old Robeya Khatun were married about eight months ago
They were arrested in raids in areas under Bayezid Police Station late on Monday night.
The suspected rapists have been identified as Osman Gani, 22, Nezam Uddin Mintu, 25, and Alamgir Hossain, 35.
OC Mohammad Mohsin said they were looking for two others accused in a case started by the victim over the incident that reportedly occurred early on Saturday.