India, Dec. 21 -- Air pollution levels in Delhi edged close to the "severe" category on Sunday as dense smog, biting cold and thick blankets of fog swept across large parts of northern India.

Delhi's air quality index (AQI) rose sharply through the day, touching 410 at 11 pm, breaching the "severe" threshold in the night. By 6:30 am on Sunday, the AQI showed marginal improvement but remained near-severe at 396, according to the ministry of earth sciences' Air Quality Early Warning System for Delhi.

The system's forecast warned of persistently hazardous conditions, stating: "The air quality is likely to be in the Severe category from 20.12.2025 to 22.12.2025. The air quality is likely be in the Very Poor category on 23.12.2025."

Accordi...