Doctors in Delhi, India, declared a public health emergency on November 7, warning people to stay indoors and prompting school closures, according to the Indian Express, as air pollution breached safe levels.

In a video, Doctor K K Aggarwal, National President of the Indian Medical Association, said readings on the country’s air pollution AQI index has exceeded 1,000, warning that when readings were above 150 strenuous exercise should be avoided, and for readings above 400 it was best to stay indoors.

“Delhi has become a gas chamber,” Arvind Kehriwal, Delhi’s chief minister, tweeted on that date, blaming the pollution on crop burning in adjacent states. Credit: Instagram/Vinayak Srivastava via Storyful