India, Jan. 4 -- The Capital's air quality worsened further on Sunday morning, with the air quality index (AQI) hovering near the upper end of the 'poor' category. The AQI stood at 298 at 8 am, up from the 24-hour average of 267 recorded at 4 pm on Saturday, according to data from the Central Pollution Control Board (CPCB).

The India Meteorological Department (IMD) had issued a yellow alert for Sunday, warning of moderate to dense fog in the early hours of the day. However, no significant impact on visibility was observed in Delhi, even as visibility dropped below 100 metres in parts of north India.

According to flight tracking website FlightRadar24, Delhi airport recorded at least 170 flight delays on Sunday morning. Airport officials ...