Some measures are part of the routine but their combined effect is chilling: mobilisation of nearly seven lakh personnel including police teams, observers, invigilators and examination staff across the country; the Indian Air Force flying more than 200 sorties to transport the question papers to various parts of the country; introduction of Aadhaar-based biometric verification and face authentication; two-layer frisking; CCTV surveillance and deployment of mobile signal jammers at the examination centres; and the setting up of the command-and-control centres at the NTA headquarters, the ministry of education, central institutions, state-level monitoring centres and district collectorates to oversee the examination in real time