Riazul Sarkar, the man arrested in Bihar in connection with the Mumbai serial blasts, may have links with the Harkat-ul-Jihadi based in Bangladesh, according to sources in the Intelligence Bureau.
But the agency doesn't have too many relevant details about the alleged link, they said.
Riazul's remand may be extended since the National Investigation Agency wants to question him.
Riazul, who is fluent in Kannada and Bengali, furnished a false address to the investigators, say sources.
"We are not suggesting that he is involved with the case. There are certain points that we still need to ascertain about whether he had any real link to the HuJI. The HuJI and the Indian Mujahideen are very closely linked and their cadres help each other cross the border," said an official involved with the investigating agencies.
Meanwhile, the police have zeroed in on IM members across the nation. They are questioning one Haroon, who is lodged in a Kolkata jail.
Haroon, suspected to be an IM operative, was picked up in June by the police after a tip-off by the IB. Apart from questioning him about the present case; the police are also trying to find out details about his linkages to sleeper cells and modules in Kolkata.
"There is a lot of focus on the modules from Kolkata since certain leads indicate that some of the men involved in the blasts could have come from there. Even during the Varanasi blasts, the foot soldiers had managed to slip out through Kolkata. The close links between the IM and the HuJI also make Kolkata a hub for such operatives," said the official.
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