India fog disrupts flights and trains 2 January 2013 Last updated at 07:12 Air and rail traffic has been disrupted in India by dense fog which has enveloped the capital, Delhi, in recent days. On Wednesday more than 30 flights were either cancelled or diverted, with at least one international flight directed to land in Mumbai. On Tuesday more than 100 flights were affected as visibility fell to near-zero levels, officials said. Disruption due to fog in winter has become routine in north India. Dozens of trains were also delayed by the poor weather. Fog started to descend on Delhi airport before midnight on Tuesday and thickened early on Wednesday morning, the Press Trust of India (PTI) reported. Runway visibility dropped to less than 25 metres at the third runway, forcing authorities to suspend operations there, the agency quoted airport sources as saying. On Wednesday, an Air India flight from Hong Kong was diverted to Mumbai while seven flights were cancelled. The Meteorological Office says that cold and foggy conditions will continue for the next few days. Dense fog has also enveloped many parts of the northern states of Rajasthan, Punjab and Haryana, reports said.