ATS chief Rakesh Maria said two men from Darbhanga in Bihar, 22-year-old Naqi Ahmed Sheikh and 23-year-old Nadeem Akthar Sheikh, had been arrested for their roles in the conspiracy. They had “abetted” the crime with “complete knowledge” and had helped steal the two-wheelers used in the attacks, he said.

A third man, Haroon Rashid Naik, 33, of Mumbra, who was already in custody in connection with a fake currency case, would also be charged for the attacks, Maria said.

Naqi is the same man who was questioned over 20-odd days by the Delhi Police over December and January before being allowed to go. Top Delhi Police sources on Monday rejected the Maharashtra ATS contention that Naqi “abetted” the 13/7 attacks. They said Naqi was only an “informer” who might have led investigators to Yasin Bhatkal. “Had he been involved, we would have been the first to arrest him”, said a source who has been tracking the Indian Mujahideen closely.

Maria said a hunt is on for Bhatkal and two other men — identified as A and B — who had lived in a house in Mumbai’s Byculla area. The ATS, he said, had found evidence and financial transactions showing that the three blasts had cost the perpetrators Rs 10 lakh. The explosives, he said, had been packed in a cloth bag before being lugged in trains from Delhi.

The evidence against Naqi, Nadeem and Haroon includes the Byculla house they rented; four stolen two-wheelers along with their duplicate keys; a helmet owned by the owner of one of the vehicles, which was allegedly found on Naqi and Nadeem; and clothes left behind by the accused in the Byculla apartment along with a computer and details of the money trail, Maria said.

Two scooters were used in the 13/7 attacks; two motorcycles were kept for future attacks, Maria said.

The ATS has invoked several sections of the Unlawful Activities (Prevention) Act against all three for allegedly conspiring, planning and aiding the blasts. In addition, charges connected to hawala transactions have been slapped on Naqi. The ATS has also moved an application seeking the transfer of Haroon, who was arrested in August in a fake currency case.

Around 40 officers and 113 ATS personnel were still investigating the case, Maria said. The ATS travelled to 18 states, more than once to some, and questioned 12,373 witnesses he said. They also analysed CCTV footage from 180 CCTV cameras at and around the blast sites, from which the first leads emerged.

“Success was achieved,” Maria said. “We were able to pinpoint the perpetrators of the crime. A lot of stress went into tracing the financial trail, where the money was sent, who had helped receiving and providing the money and we can now say the financial trail of the blast has been fully covered.”

Naqi allegedly became friends with Bhatkal around 2008, and came to Mumbai’s Madanpura area some time in September-October 2010. The ATS found that Naqi and Nadeem stole the scooters used at Zaveri Bazaar (Grey Honda Activa MH 01-WA 3042 stolen from Khadikar Road) and Opera House (Maroon Honda Activa MH 01-MJ 6502 stolen from outside Harkisondas Hospital), Maria said.