The arrestee was identified as Abu Raihan of Rahelapur village in the Sadar upazila.
Officer-in-Charge of Kotwali Police Station Moniruzzaman said the victim is an eighth grader who used to cook in the madrasa.
Raihan took the girl to his house on August 9 and violated her, the OC said.
The victim’s mother filed a case on Monday night over the matter, he said.
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