A PACKED passenger plane has been evacuated after an alleged hijacking message was found in the toilet just moments before take-off.

The chilling handwritten note was reportedly scrawled on a mirror in the bathroom of an Air India flight with the discovery sparking a major police response.

The flight, scheduled to operate from Kolkata to Mumbai, was dramatically halted before take-off on Wednesday at Netaji Subhas Chandra Bose International Airport.

Airport authorities immediately evacuated all passengers from the aircraft as they moved the plane to an empty part of the airport.

Security agencies rushed onboard to complete a thorough search of the aircraft.

Police have not said if they found any suspicious items.

According to airport officials, the flight had been scheduled to depart at 10.20am when the alert was first raised.

Kolkata airport director Vikram Singh said the message allegedly claimed the aircraft would be hijacked at 11.10am.