In April-May, the Delhi police and the Anti-Terrorism Squad of the Mumbai police launched a joint operation.
The aim was to nab two of Pakistan-based Lashkar-e-Tayiba's most important operators in India.
The operation failed.
Two months on, investigations into the Mumbai blasts have revealed that if the two -- Rahil Sheikh and Zabiuddin Ansari had been arrested then, the July 11 tragedy could have been averted.
Police sources said Rahil and Zabiuddin, who are the prime suspects in the Mumbai blasts, are suspected to have moved to Pakistan from where they are coordinating LeT activities in Mumbai.
Being a prime suspect in the October 2005 Delhi serial blasts, Rahil was already wanted by the Delhi Police. With his LeT activities in Maharashtra coming under the scanner of the Anti Terrorism Squad, the two forces worked out a secret plan to nab him, sources said.
Rahil was then hiding at a place in central Mumbai. However, when the Delhi Police-ATS teams surrounded the house where he was holed up, Rahil apparently realised the plan and jumped from the first floor of his hideout, making good his escape, senior police officials said.
Similarly, when the ATS launched an operation to trace an arms cache moving near Aurangabad in Marathwada region in May, Zabiuddin Ansari alias Zaby was also accompanying the LeT operatives, sources said.
However, as the police vehicles chased the LeT vehicles, Zabiuddin allegedly escaped, and in the days ahead, moved to Pakistan via Bangladesh, sources said.
Top intelligence officials said the arrest of the two key LeT operatives would not only have helped police expose the LeT network in Mumbai and parts of the state, but could have probably averted the July 11 serial train blasts.
Meanwhile, Faiyaz Kagazi - a close aid of Zabiuddin - whom the ATS was searching after the serial blasts, is also suspected to have escaped to Pakistan, sources added.
It is suspected that after their escape to Pakistan, Rahil and Zabiuddin planned the July 11 blasts to avenge the crackdown by police and LeT members in Maharashtra.
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