The kidnappers took him to an under-construction building in Bosila, where two more men joined them, said MD Abul Kalam Azad, chief of the Mohammadpur police station, citing details of the case.
One of them frisked her, while the other four, including the rickshaw puller, raped and assaulted her.
Hearing his screams, the people around took him out of the building. However, the criminals managed to escape.
They brought the woman to Dhaka Medical College Hospital for treatment.
The deputy commissioner said that the police had earlier arrested 19-year-old Shaheen Khan in connection with the gangrape incident.
“The rapist took away the mobile phone of the victim on the day of the incident. Shaheen Khan recovered the phone at Bosila and started using it.
The deputy commissioner said that the police arrested Shaheen Khan with a mobile phone on January 4 at Chad Udyan in Mohammadpur.