With hours to go before the grand Republic Day parade in New Delhi, security agencies have turned the venue into a veritable fortress with hundreds of barricades and commandos in place and sharpshooters on rooftops to thwart any possible terror attack.
Every inch of Vijay Chowk, from where the parade begins, and Rajpath, where the dignitaries, including President Pratibha Patil and special guest French President Nicolas Sarkozy, will be seated, has been thoroughly checked by police sniffer dogs and commandos and sanitised.
Special Indian Air Force helicopters will be keeping vigil over the parade venue on Republic Day on Saturday as well as on traffic movement in other parts of the city.
According to Delhi Police, 34 companies of central paramilitary forces, 140 companies of the Delhi Armed Police (DAP), sleuths of the Crime Branch, Special Cell and Special Branch are conducting special checks on suspects, especially in central and east Delhi and areas bordering the capital.
The 12-km-long parade route from Vijay Chowk at Raisina Hills to the 16th century Red Fort will see over 26,000 security personnel deployed along it.
Apart from the hundreds of security barricades along the route and sharpshooters on rooftops, elite commandos and spotters - those trained to spot suspicious looking people - will also be keeping watch.
Delhi's airspace will be closed for a few hours on Saturday morning with over a dozen fighter aircraft waiting at Palam and other nearby air bases to tackle any rogue plane.
Several anti-aircraft guns have been set up at undisclosed locations with the men scanning the horizon around India Gate and Rajpath to engage any airborne target.
"Elaborate air defence measures, including the deployment of anti-aircraft guns, have been taken to check any intrusion of air space," Delhi Police spokesperson Rajan Bhagat said.
Bhagat said: "Although this time there is no specific threat, security arrangements are very similar to last year's."
However, sources said, the Intelligence Bureau has warned Delhi Police and other security agencies of a possible strike from the terror outfits Lashker-e-Taiba (LeT) and Harkat-ul-Mujahideen.
Besides cordon and search operations around the venue of the Republic Day celebrations and vehicle checks, the security forces are also using electronic surveillance gadgets like closed-circuit TV cameras to keep an eye on any suspicious movement in the city.
Several roads in and around India Gate, which the parade will pass, have been blocked for security reasons.
Delhi Police have also asked all citizens, including shopkeepers, security guards, auto rickshaw drivers, bus drivers, conductors and parking lot attendants to keep a strict lookout for suspicious looking people and objects.
"We have requested members of residents' welfare associations, second hand car dealers, shopkeepers, street vendors, property agents, guesthouse owners and other citizens to become the eyes and ears of the police," said Bhagat.
"We have requested them to be alert as they come across scores of people everyday," Bhagat added.
Police have sounded a high alert in all 10 districts of the city and detained several people in the past few days, mainly those cyber café owners who have failed to furnish details of internet users, and house owners who have not given details of their tenants.
The Indian government has also asked airports around the country to adopt "heightened security measures" after an intelligence tip-off that the United Liberation Front of Asom (ULFA) may attempt to hijack an aircraft to free their colleagues from jails.
The Bureau of Civil Aviation Security (BCAS) has alerted airports in the four metros, the northeast, as well as in Hyderabad and Bangalore and some international airports like in Amritsar as potential targets ahead of Republic Day.
According to a BCAS official, the ULFA hijack attempt could likely be in the northeast.
"The ULFA is prepared for this daring act to draw the attention of the international community," said a senior home ministry official.