The National Investigation Agency believes a Lashkar operative, who played a major role in coordinating the 26/11 attacks, operates under three aliases and is a wanted terrorist in four countries.
While the US Federal Bureau of Investigation and the Italian police refer to him as Sajid Mir, he is Abu-al-Qama for the Indian police. The Pakistan authorities, who claim to have arrested him, call him Zarar Shah.
According to Intelligence Bureau sources, Mir has been a member of the Lashkar for nearly 15 years. He is considered to be Lashkar leader and 26/11 prime accused Zaki-ur Rehman Lakhwi's closest aide and responsible for setting up the outfit's information technology cell.
He is also believed to be trusted by officers in Pakistan's Inter Services Intelligence directorate.
Mir alias Qama alias Shah, who reportedly took charge of the Lashkar's trans-continental operations in 2005, supervised the transaction of funds for the Mumbai attacks. He also kept in touch with terror suspects David Headley and Tahawwur Hussain Rana, who were arrested by the FBI in Chicago last month, the father-son duo arrested in Italy on Saturday, and 26/11 accused Sabahuddin Ahmed and Fahim Ansari.
All these individuals operated on a need-to-know basis. Mir alias Qama alias Shah ensured that they were unaware of each other's activities.
While he instructed Sabahuddin Ahmed to ask Fahim Ansari to survey possible terror targets in Mumbai, he is believed to have told Headley and Rana to conduct another reconnaissance of likely targets in the city.
Ahmed and Ansari may have been unaware of Headley and Rana's activities, IB sources said.
On the basis of information provided by Ansari, Mir instructed both Rana and Headley to conduct a more complete analysis of the targets, including compiling video footage.
In February, the Pakistan government claimed it had arrested a Lashkar operative named Zarar Shah who knew Ajmal Kasab, the surviving 26/11 terrorist, and his nine associates.
However, Pakistan turned down a US request to interrogate Shah.
Information available with the IB suggests that Zarar Shah is actually a low-ranking Lashkar operative named Abu Wajid, and not the real Mir. Indian officials have requested Pakistan for a photograph of Shah, but their request has been denied.
The ISI, IB sources said, wants to protect the identity of the real Mir as he is aware of the agency's role in spreading global jihad.