Chota Shakeel, a close associate of Dawood Ibrahim [Images], has been given the responsibility of killing Mohammad Ajmal Amir Kasab [Images], the lone terrorist arrested during the terror attack on Mumbai [Images], according to Intelligence Bureau sources.

Earlier in the day, Joint Commissioner of Police (Crime), Rakesh Maria [Images] had told the media, "We have received intelligence inputs stating that Kasab's life may be under threat from the underworld".

IB sources have revealed that the Lashkar-e-Tayiba [Images] has asked Shakeel, a close associate of underworld don Dawood Ibrahim, to kill Kasab. Shakeel is currently hiding in Pakistan, said IB officials, under the patronage of the Inter Services Intelligence and the LeT.

The IB learnt of the LeT's plans concerning Kasab after it intercepted a telephone call from across the border. The call, made by a Lashkar operative, indicated that Kasab's murder was being planned by the LeT in Pakistan.

The IB also learnt that the contract for Kasab's murder had been handed over to Dawood Ibrahim's gang, which continues to operate in Mumbai, on the instructions of the underworld don, who is also hiding in Pakistan.

Police officials believe that Shakeel will use the local module of his gang in Mumbai to gain access to Kasab, who has been kept in an undisclosed location.

Kasab, who hails from Faridkot in Pakistan, is the most vital proof that India possesses about the terror attack originating from its neighboring country. His death would be an irreparable setback for India's fight against terror.

The IB has now advised the Mumbai police to beef up Kasab's security arrangements and monitor him round the clock.