IB sources told rediff.com that Sheikh, who slipped into Pakistan earlier, has now returned to Birmingham, where he was said to be living earlier.
A Bureau agent said Sheikh is wanted in the July 11, 2006 train bombings in Mumbai.
Trained as a computer engineer, Sheikh's brothers Faisal and Muzammil Shaikh have already been charged in the 2006 bombings.
The Mumbai Anti-Terrorist Squad has been trying to trace Sheikh since the train bombings, but he gave the ATS the slip on at least two occasions.
A Mumbai ATS officer suspects that Sheikh helped raise funds for the Mumbai attacks. The ATS claims he raised Rs 1,462,379 for the 2006 bombings.
The financer of every attack is usually in touch with the planners behind the acts of terror.
IB sources say Sheikh's telephone records, which they are in possession of, indicate that he has been receiving calls from Saudi Arabia, Dubai, Nepal and Bangladesh. The intercepts suggest that he was acting as the point man to collect funds and pass it on to the Lashkar-Tayiba, which carried out the attacks.
The latest intercept suggests that Sheikh sent the money to the Lashkar's chief recruiter Azam Cheema.
Two days before the Mumbai attacks, Sheikh was reported arrested in the United Kingdom. However, the Central Bureau of Investigation denied the report. IB sources say that after he eluded Indian law enforcement agents after the 2006 attacks, Sheikh, who used to work in the IT industry, moved in and out of Britain. He also traveled to Pakistan.
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