Dense fog swathed large parts of northern India on Tuesday for the third straight day of an intense cold wave, reducing visibility to disrupt more than 160 flights.
As many as 128 flights from the international airport in New Delhi, the capital, were delayed, with 33 cancelled, aviation site Flightradar24 showed, an effect that cascaded through flight schedules nationwide.
Visibility at the airport stood at 50 m at 8:00 am, weather officials said, predicting similar conditions until the end of the week.
New Delhi's lowest temperature this winter was 3.3 degrees Celsius on Monday, when low visibility and dense fog caused the delay of as many as 500 flights and the cancellation of 87.
Angry passengers argued with airline staff in images on television and social media, with one video showing passengers eating dinner as they waited on the tarmac for a delayed flight.
On Monday, the aviation minister said authorities were hastening efforts to use an additional runway, equipped with the CAT III navigation system that enables aircraft to land despite low visibility.


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