Deputy Commissioner Bijoy Bosak of Chattogram Metropolitan Police said the victim was returning home on a rickshaw from Bahaddarhat Bus Terminal in the morning.
The miscreants kidnapped her when she reached Moulvipukurpar area and gang-raped her in a nearly building, Bosak said.
The victim was sent to Chattogram Medical College Hospital (CMCH) for medical tests, he said.
A series of recent rape incidents have sparked countrywide protests. The government on Thursday said it would amend the law to ensure the maximum penalty for rape.
Ain-o-Salish Kendra (ASK) said that between January and September 2020 nearly 1,000 rape cases were reported, including 208 gang rapes.
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