Intelligence Bureau officials say the Mumbai terror attacks were the handiwork of the Pakistan-based Lashkar-e-Tayiba in association with some 'home-grown terrorist groups' from India.

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IB sources say the E-mail sent out in the name of a little-known outfit, Deccan Mujahideen, has been traced to Russia [Images].

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Both IB and RAW officials are examining the mail apart from grilling the terrorists who have been nabbed in Mumbai.

IB sources also say that terrorists came in directly from Karachi into Mumbai using the sea route.

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The intention, the IB says, is very clear.

It was aimed at destabilising the financial capital of India. Moreover, they also wanted to avenge the arrests of the Indian Mujahideen [Images] cadres in Mumbai.

The IM, which is a wing of the Students Islamic Movement of India, works directly under the supervision of the LeT, IB sources added.