Akhtar, who was arrested with Bhatkal, revealed to the investigators the details of the places they had visited in Hyderabad before carrying out the blasts. He also confessed to his role in the Dilsukhnagar blasts and agreed to have planted the explosives on bicycles.
The NIA officials took Akhtar to a few places at Bhadaurpura, where he resided and allegedly made bombs with some others.
Bhatkal and Akhtar were arrested by the Bihar Police on August 28 and are allegedly involved in several bomb blasts in different parts of the country.
The twin blast at Dilsukhnagar had claimed 18 lives and injured many.
Bhatkal too, during his interrogation, accepted to have planning terror attacks across the country, including the Bangalore Chinnaswamy stadium blasts.