“Following the Mahabodhi temple blasts on July 7 this year, we were asked to step up vigil at all key installations. So, we have increased scrutiny and put more men on duty. Further, the airlines are also doing their security checks now. Though we are not doing anything specific, we have tried to increase the layers of observation,” the official added. “There is no specific threat to Chennai airport. It is only a generic alert. Airports are always vulnerable places and since sensitive airstrips could be targeted, we increase vigil whenever the intelligence bureau alerts us,” said an airport official, who added that security at Chennai airport has been beefed up. In general, airport authorities curb visitors’ movement and also increase more layers of security checks, a week before Independence Day, Republic Day and during December on account of Babri masjid demolition day.But now, with the new terminals out of bounds for visitors, security agencies can heave a sigh of relief. With memories still vivid of the July 24, 2001, Bandaranaike airport blast in Sri Lanka where 26 aircraft were either damaged or destroyed in an LTTE attack, the month of July has always been hectic for security agencies in India.This year, July 21 and July 25 have been identified as days of potential threat. In Chennai, too, security has been beefed up, the Deccan Chronicle reported.