Noore Alam confessed the rape to the court after his arrest
The law minister informed reporters after a programme at a hotel in Dhaka on Wednesday that this was possible.
On July 8, 13-year-old Rajan was tortured to death at Kumargaon. The murderers posted the video on the internet, triggering an uproar.
Locals caught and handed over to the police the suspects -- Muhit Alam, Ali Haider and security guard Moyna Mia.
Muhit’s brother Kamrul Islam was caught in Jeddah.
Fifteen days after the murder, the law minister had said the chargesheet would be submitted within three to four days.