Two sisters were gang-raped by a group of youths at Noannoi village in Noakhali Sadar upazila on Thursday night.
A case has been filed against 11 identified people and 3-4 unidentified ones with Sudharam police station in this connection.
The accused include Sumon, 22, Javed, 19, Helal, 19, Akbar, 22, Sujan, 19, Lutu, 19, Bali, 19, Mamun, 20, Shakil, 19, Rashed, 20, and Riaz, 20.
Police, meanwhile, arrested prime accused Sumon on Friday, reports UNB.
Officer-in-charge (Investigation) of Sudharam Police Station Mirza M Hasan said the elder of the victims, hailing from Gorapur village, had been in a relationship with Sumon.
On Thursday evening, Sumon called her over her mobile phone and asked her to come to Noannoi village. Later, she along with her younger sister went to the Noannoi village around 7pm.
As the two sisters reached there, Sumon and his accomplices forcibly took them to an isolated field and raped them by turns.
Hearing screams of the sisters, locals rescued them, but the perpetrators fled.
The victims were sent to hospital on Friday morning for medical examination, the OC said.