CISF commandos on vigil outside Bangalore airport on Thursday. (PTI)

Dec. 4: Aerodromes across the country went on high alert following intelligence reports warning of attacks on Delhi, Bangalore and Chennai airports between December 3 and 7.

Airports and airlines have introduced random second checks on passengers and baggage, air marshals have been asked to restrict visitors and all passengers have been asked to carry ID proof. Restrictions have also been placed on carrying liquid and gels on board.

A high-level committee on security met in the capital today after Delhi airport received an email threatening strikes on the three airports, sources said.

An official, requesting anonymity, said: “We had specific intelligence inputs that militants from Pakistan or Afghanistan were planning to attack airports ahead of the anniversary of the demolition of the Babri Masjid.” December 6 will mark the 16th anniversary of the demolition.

After a programme in Delhi to mark Navy Day, air force chief Fali Homi Major said the force was prepared to respond to defence minister A.K. Antony’s high alert on “terror from air”.

“This is based on a warning which has been received by the government and we are prepared as usual,” he said.

IAF fighter jets have been put on standby at major airports.

Quick reaction and disaster management teams have been activated at the airports under threat, and bomb disposal squads and sniffer dogs have been brought in. The National Security Guard has also been put on alert.

Special armed teams have been asked to patrol the “city-side”, the technical term for non-operational areas in airports, as well as the periphery such as cargo complexes.

The civil aviation ministry today held a series of meetings with officials of the Bureau of Civil Aviation Security (BCAS), intelligence agencies, home ministry and the Central Industrial Security Force (CISF).

Officials said the aviation security bureau had instructed the CISF to introduce a second layer of baggage checks and body searches. Sources in the bureau said the special screening would continue till at least the end of this month.

Instructions have been given to check the antecedents and background of employees of airline contractors, sub-contractors and airport operators.

Airports have been asked to keep a watch on the movement of screened cargo to and from aircraft and disposal of prohibited items detected in passengers’ baggage.

Officials said as a long-term measure, they were trying to streamline airport access through smart cards, introduce passenger profiling and strengthen the cockpit doors of state-run aircraft.

Security agencies have started installing more closed-circuit television sets at airports. They have also asked airlines to set up systems inside planes to communicate with ground staff in case of a hijack, sources said.

There have been intelligence warnings of hijack of planes flying out of the Delhi, Bangalore and Chennai airports.

Officials said explosive vapour detectors had been procured for the CISF to carry out random checking of passenger baggage and ground bomb killer blankets had been brought in to minimise the impact of an explosion.

Delhi airport has also decided to bring in a four-layered perimeter intrusion detection system by the middle of next year.

The security drill was the most intense in Chennai, where fliers were surprised by random vehicle checks and CISF men in battle gear behind sandbags.

“I’ve never encountered anything like this. I thought I had arrived at Srinagar airport,” said businessman Vivek Raghavan.

Domestic passengers have been advised to reach the airport three hours before their flight time for the next few days.

“We have positioned 200 extra personnel along with the 600 regular ones,” Jayanth Murali, the CISF DIG, said.

At the new Bangalore international airport, entry of visitors into the terminal has been stopped. “Quick reaction teams of the CISF have also been put in a high state of readiness,” an official said.