India has been warned by its intelligence agencies that militant group Lashkar-e-Taiaba (LeT) could target its nuclear installations, National Security Adviser MK Narayanan said on Friday. Narayanan described it as a "very serious threat"."There is information that maybe one of our atomic energy installations could be the target," he told CNN-IBN news channel. "It's (an) LeT operation... it is a very serious threat," he said. India has pointed a finger at the LeT for a series of bomb attacks on commuter trains in Mumbai on July 11 that killed 183 and wounded more than 800.