Lucknow, Jan. 20 -- The Sarojininagar police on Monday lodged an FIR against an unknown person for a bomb threat scribbled on a tissue paper inside the aircraft lavatory. This followed a Delhi-Bagdogra IndiGo flight making an emergency landing in Lucknow after the hoax. The FIR lodged by IndiGo security officer Vipin Tripathi reported that flight 6E-6650 received a mid-air alert at 8.45 am after a crew member found a handwritten note reading 'Bomb on the plane' inside the rear washroom. The pilot informed Air Traffic Control and diverted the aircraft to Lucknow, where it landed at 9.17 am and was moved to an isolation bay. Quick reaction teams, bomb disposal units, CISF personnel, and airport officials cordoned off the area and conducted a detailed inspection. Investigators later declared the threat a hoax, and the aircraft was cleared for departure to Bagdogra at 4.30 pm....