The Delhi Police has arrested Abu Hamza alias Saeed Zabi alias Zabi Ansari, an Indian Mujahideen operative who is suspected to have been one of the handlers who was giving instructions to the 26/11 terrorists in Mumbai.
The Delhi Police and the Intelligence Bureau had been keeping a watch on Hamza's movements.
After getting a tip-off that he was returning to India, the police arrested Hamza from the Delhi airport four days back itself.
His arrest was confirmed on Monday morning.
With Hamza comes a host of information ranging from the IISC attack and the more important 26/11 attacks.
Sources in the Intelligence Bureau say that Hamza, who has been heading the Lashkar-e-Tayiba operations in Kashmir since a year, was looking to conduct a recee on some places.
Hamza will remain in police custody till July 5.
According to the officials associated with the probe, Hamza had told Lashker terrorists carrying out attack in Nariman House to convey to the media that the "attack was a trailer and the entire movie was yet to come".
In the intercepted tapes, Hamza was also heard using typical Hindi words like prashasan (government) and was directing the terrorists to conceal their Pakistani identity and identify themselves from Deccan Mujahideen hailing from Toli Chowk in Hyderabad.
His presence was also stated by Ajmal Kasab, the lone terrorist arrested during the Mumbai attack, in his deposition before a special court. He told the court that one person by the name of Abu Jindal had tutored 10 terrorists on how to speak Hindi.