Andhra Pradesh police has said that Mohammad Shahid alias Bilal, one of the most wanted terrorists, had masterminded the twin blasts on August 25, which killed 43 people.
Bilal is also the prime accused in the Mecca Masjid blast on May 18, 2007, which killed nine people.
According to the police, Bilal, who is believed to be operating from Pakistan and Bangladesh, allegedly worked for terrorist outfits like Lashkar-e-Tayiba, Jaish-e-Mohammad and Harkat-ul- Jihad-Islami.
The investigators believe that about 10 kg of RDX might have been smuggled into Hyderabad from Bangladesh as far back as February 2007.
Bilal, a native of Hyderabad, and three Pakistanis had played a key role in the smuggling of RDX to the state capital, the sources said.
He had fled the city about six years back after a bomb blast at a Sai Baba temple in Dilsukhnagar, Hyderabad.
The Special Investigation Cell, set up to probe the explosion in the Mecca Masjid, had gathered information about the smuggling of RDX after narco tests on some of the suspects during the course of investigation.
Police will soon file cases against 15 persons for their alleged involvement in the smuggling of RDX.
Meanwhile, the SIT probing the August 25 blasts, was questioning several suspects, including some Pakistani and Bangladeshi nationals overstaying in the city even after the expiry of their visas.
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