The PM's programme was, however, not cancelled and he would leave for Kokrajhar by an Indian Air Force helicopter after routine security checks, the sources said.
The PM was scheduled to review the situation with the Bodoland Territorial Area District authorities and visit two relief camps. Earlier, Dr Singh arrived by a special aircraft from New Delhi.
Assam Governor J B Patnaik, Chief Minister Tarun Gogoi, his cabinet colleagues, Chief Secretary N K Das and Director General of Police J N Chowdhury were present at the airport.
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