The Centre has advised all states bordering Maharashtra to be fully alert in the wake of intelligence inputs that terrorists may target Chhatrapati Shivaji International Airport in Mumbai by using small aircraft.
Directors General of Police of Maharashtra, Gujarat, Madhya Pradesh, Karnataka, and Goa apart from the CISF have been asked by central security agencies to remain on high alert to foil any possible terrorist design to attack the Mumbai airport, sources said.
A specific input suggested that terrorists may try to use a small aircraft or a helicopter to target the country's busiest airport, the sources said.
The Centre asked the police chiefs to put small aircraft and private helicopters under strict vigil before they are allowed to fly, they said.
The sources said the Centre has also directed that unused airstrips and private helipads be brought under the watch of local law enforcement agencies and put under strict vigil.
Following the advisory, the states concerned have taken a number of steps to intensify security in some specified areas, the sources said.