The arrestee was identified as Raihanul Islam alias Raju, assistant sub-inspector of Rangpur DB police.
ABM Jakir Hossain, superintendent of Rangpur Police Bureau of Investigation (PBI), said ASI Raihanul was suspended as he was the key accused in the case. He was attached to the District Police Lines.
A team of police arrested Raihanul acting on the statement of the victim on Wednesday night.
He will be produced before court on Thursday.
According to the case statement, Raihanul developed a love affair with the victim and took the girl to the house of another accused of the case Meghla on October 23.
Raihanul also "had sex" with the girl on that day.
Two more young men reportedly violated the girl the following day at Meghla’s house.
The victim then filed a case against them. Police later arrested Abul Kalam Azad, Babul Hossain, Meghla and Shampa in this connection.
On Wednesday, the victim gave her statement before the Rangpur Chief Judicial Magistrate’s Court.
All the arrestees made confessional statements before the court.
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