New Delhi: Nearly 50 domestic and international flights of Indian carriers received bomb threats on Tuesday, taking the total number of flights that have received the threats since Monday night to around 80, according to sources. The sources in the know said 13 flights each of Air India and IndiGo, over 12 flights of Akasa Air and 11 flights of Vistara received the threats on Tuesday. On Monday night, 10 flights each of Air India, IndiGo and Vistara had…