Indian Navy sources said one ship in Bay of Bengal and another two in Andaman Sea have been put on standby.
Along with these, a P-8I aircraft has also been put on standby. The aircraft is used for maritime reconnaissance and anti-submarine warfare operations.
"The assets have been put on standby in view of the gravity of situation. They will be rushed into service as and when any order is issued," the sources said.
A Singaporean transport official said Flight QZ8501 lost contact with Jakarta Air Traffic Control just after 07.24 hours local time.
The aircraft was in the Indonesian Flight Information Region (FIR), more than 200 nautical miles southeast of the Singapore-Jakarta FIR boundary, when contact was lost, Civil Aviation Authority of Singapore said.
Contact with the plane was lost 42 minutes after takeoff.
No Indian national was on board.
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