INDIA – Air traffic was on Monday Dec. 15, disrupted amid dense fog caused by air pollution in Delhi India.

Airlines operating at Delhi airport wrote on social media company X that “poor visibility” due to dense fog impacted flight operations for all airlines.

The country’s largest carrier IndiGo said the capital was seeing its “first hint of winter fog this morning, and visibility around the airport is currently reduced.”

While Indian officials are yet to reveal the number of flights cancelled and delayed, Indian broadcaster NDTV, quoting Flightradar24, said around 100 flights were cancelled and over 300 delayed at Delhi airport.

The disruptions of flights come at a time when the national capital has been battling toxic pollution levels for the past few days.

Data from India’s Central Pollution Control Board showed the Sunday evening reading of the air quality index (AQI) at 461. An AQI reading between 201 and 300 is considered poor, followed by very poor from 301 to 400, and severe between 401 and 500. According to experts, AQI in the severe category affects healthy people.

Authorities have initiated anti-pollution measures to stem the smog and urged residents, especially vulnerable people, to stay indoors.

The Singapore High Commission in New Delhi on Monday also issued an advisory asking its nationals to pay heed to this advice by the authorities that urged residents to stay indoors, especially children and those with respiratory or cardiac ailments, and to use masks if stepping out.

Air pollution has become a persistent problem in New Delhi, and it gets worse during the winter, when farmers in nearby areas burn crop stubble and add to the emissions of coal-fired plants and industrial units around the city.