Jaipur, Dec 28 : Over half-a-dozen airport directors, including those in Delhi and Jaipur, have received emails threatening to bomb the airport and planes. Sources said that an email came at around 10:23 pm on Wednesday night in which it was claimed that Delhi, Jaipur, Lucknow, Chandigarh, Mumbai, Chennai and Ahmedabad airports would be bombed. There was a stir at Jaipur Airport after receiving the threatening email on the official customer care ID. On receiving the information, the CISF officials took charge and with the help of the local police, they started investigating, combing and sanitising the airport and the flights landing there. The police have not found any suspicious object in their search so far and the CISF has now filed a written complaint with the Jaipur Airport police station. Meanwhile, a probe is on to ascertain as to who sent the email to the airport directors on the ID of the customer care. /IANS