The anti-terrorism squad (ATS) of Gujarat police claimed on Friday Tauseef Khan better alias Atik, who was arrested from Gaya on Wednesday, was the mastermind behind the July 2008 serial bomb blasts in Ahmedabad.

A total of 56 people were killed and over 200 others were injured in simultaneous bomb explosions at 21 places in Ahmedabad on July 26, 2008.

A four-member ATS team from Gujarat reached Gaya on Friday to interrogate Tauseef, also known as Tauseef Sagar Khan Pathan, and his two associates. A senior police officer said 35 terror-related cases were pending against Tauseef, a resident of Juhapura in Ahmedabad. While 20 cases were lodged against Tauseef in Ahmedabad, the remaining were registered in Surat. 'The list of cases pending against him in Gujarat has already been submitted to Gaya police,' said a member of the visiting police team.

The officer, requesting anonymity, said Tauseef was the brain behind the Ahmedabad blasts. Once considered close to the main operatives of Harkat-ul-Jihad-al-Islami (HuJI) such as Mujeeb Sheikh who was killed in a police encounter in Madhya Pradesh in 2016, Tauseef was also allegedly closely associated with Indian Mujahideen co-founder Yasin Bhatkal.

Bhatkal was arrested from Raxaul near the India-Nepal border in East Champaran district, around 200km north of Patna, in 2013.

'Tauseef was engaged in forming a new module (sleeper cell) in Magadh (Gaya) region. That's why he was staying in the house of a former chief of the Students' Islamic Movement of India (SIMI) ever since he left Ahmedabad following the serial blasts,' the police officer revealed.

The officer said Tauseef used to indoctrinate youths from remote villages under Dobhi block in Gaya district, where he earlier worked as a teacher of mathematics and science at a private school. Shane Khan, a resident of Shahdeo Khap village in Gaya, had allegedly helped Tauseef get a school teacher's job.

Sources said Gujarat ATS officials were trying to elicit information from Tauseef about 15 absconding operatives of different terror outfits.

Inspector-general (Patna zone) Nayyar Hasnain Khan said the three trio were produced in the Gaya chief judicial magistrate's court after interrogation. 'The court remanded Tauseef in police custody for four days,' Khan told The Telegraph .

A case under Unlawful Activities (Prevention) Act 1967 has been registered against Tauseef and his associates with the Gaya Civil Lines police station.

A senior Gujarat police officer said Tauseef, a bachelor in engineering and communication from a Maharashtra-based engineering college, worked at a software company in Bangalore and later taught at a college in Nadiad (Gujarat) before the serial blasts. He said Tauseef had set up links with SIMI before his family shifted to Ahmedabad. 'He was a committed member of SIMI and closely associated with Juhapura-based accused Alamzeb Afridi, an accused in the 2014 Bangalore blast case.'

Tauseef was arrested with his two associates on Wednesday when he refused to provide his identity proof at a cyber café in Gaya.