India's capital Delhi was covered by a thick layer of dust after a storm on Tuesday morning that led to a sharp decline in air quality levels.
The national weather office said strong winds caused by a cyclonic circulation over the western desert state of Rajasthan brought dust and sand particles to the city.
The Air Quality Index (AQI) fluctuated between "severe” and “poor” levels in many parts of Delhi, causing an increase in breathing difficulties for many residents.
An AQI reading between zero and 50 is considered good, 51 to 100 satisfactory, 101 to 200 moderate and 201 and 300 poor.
Tuesday’s readings of particulate matter (PM 2.5) — fine dust and other harmful particles that can penetrate the lungs and enter the bloodstream — were way above the World Health Organisation’s air quality guidelines, Swiss group IQAir reported.
In neighbouring Noida, the AQI reading was 179 — and the PM 2.5 concentration was 22 times the WHO's guideline, IQAir said.
The India Meteorological Department warned of more storms and rain in the city.
“Dust storm/gusty winds with speed of 40-75kph would occur over and adjoining areas of entire Delhi and NCR [National Capital Region], Jhajjar, Farukhnagar, Sohana, Nuh in Haryana,” the office said.
Delhi has high air pollution throughout the year, with air quality worsening in winter.
However, many residents in the capital were surprised to wake up to the grey skies.
"This morning I got reminded of #Interstellar movie by Delhi NCR's dust storm. Do we have to move to rings of Saturn like the movie," said Aparna Pal, a Twitter user.
"DC studios folk don't need to work so hard on CGI and sets. A Delhi summer morning now offers just as gloomy as a Gotham winter evening, providing the perfect setting for the next Batman movie," another user Ankiit Koomar said.