On Friday morning Delhi witnessed Zero visibility at Indira Gandhi International (IGI) airport. Flight operations were severely hit and atleast 150 flights arriving or departing from New Delhi was delayed by several hours. Between 6 a.m. and 9a.m. no take offs could take place . As many as 129 domestic flights and 39 international ones were delayed, many by three to five hours. Airport sources say that the delays in the morning hours will have a cascading effect on flights throughout the day, therefore, the number of flights affected will go up. From 10:45 a.m. and 12:15 a.m. there are restrictions on civilian flights due to rehearsals for Republic day on January 26.