At least 17 trains were rescheduled and 40 others were running late on Monday due to heavy fog in the many parts of north India, a railway official said.
According to the Northern Railway official, the Bhagalpur - Anand Vihar Garib Rath Express was running over 26 hours behind schedule, the Howrah Kalka Mail and Poorva Express are running 11 hours behind schedule, and the Sampoorna Kranti Express was over 10 hours late.
The official also said that no trains were cancelled.
Meanwhile, according to the Delhi International Airport Limited, which manages operations at the Indira Gandhi International Airport here, flight operations were only moderately affected and no flight was kept on hold on Monday.