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Security at the perimeter of airports has been beefed up to prevent any unauthorized entry into runways or other areas, sources said, with intelligence agencies also warning that there could be an attempt by terrorists to stage an attack like the one in the US in November 2013, when a gunman opened fire at the Los Angeles International Airport.
Anti-hijack drills are planned at airports to "revalidate processes," senior CISF officials said. The agency is also checking on its communication lines with local police and the elite National Security Guard in major cities to ensure minimal reaction time in case of an attack.
There is additional checking of passengers and their baggage at some of the major airports, including the Indira Gandhi International (IGI) Airport in Delhi.
Airport staff has been asked to check cabin baggage once boarding is completed and even airport staff is being thoroughly checked by the airport security personnel, sources said.
The CISF has emphasised that, "there is nothing to panic, this is just to ensure that the agency does not leave anything to chance," in view of the alert sounded.
Flights to Afghanistan are being monitored carefully, said security officials.
Sources have told NDTV that the threat perception is based on messages that surfaced earlier, indicating that both Islamic State militants and the Taliban could choose to target India with a possible hijack of an Air India flight to Kabul.
They said Air India could be targeted as it is the national carrier and senior India officials travel on it to Kabul in Afghanistan.
The specific alert comes amid a larger security alert ahead of US President Barack Obama's visit to India later this month. The US President will be the chief guest at the Republic Day parade to be held in Delhi on January 26.
Security had already been tightened at airports and other vital installations across the country in view of the US president's visit.
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