Thousands of gun-totting security personnel were on Delhi streets on Friday keeping a vigil to pre-empt any terrorist strike on the eve of Independence Day celebrations.
An impregnable ground-to-air security apparatus is put in place in the capital, especially near Red Fort where Prime Minister Manmohan Singh will unfurl the tri-colour and address the nation for sixth consecutive time on Saturday.
Though no specific intelligence input about a possible terror strike is there, security agencies are leaving no stone unturned to ensure an incident-free Independence Day, official sources said.
Security agencies reviewed arrangements at the Red Fort and have zeroed in on 'safety houses' to where the Prime Minister and other leaders should be taken to in case of a terrorist strike, they added.
Fourty CCTVs have been installed in and around the Red Fort to ensure incident-free function while sharpshooters of the NSG will be deployed on high-rises near the 17th century Mughal monument.
An air defence mechanism has been put in place around the venue to thwart any terror attacks even as military choppers will conduct air surveillance.