India's capital New Delhi is restricting car use to tackle toxic levels of air pollution, which have already forced the government to shut schools for the rest of the week.
The "odd-even" scheme, which allows only odd or even license plate numbers on the roads on alternating days, will be implemented on Monday for five days.
"The situation in Delhi is so bad and if the pollution can be brought down in any way, we will do it," the city's transport minister Kailash Gahlot told reporters, announcing the implementation of the restrictions Thursday.
The smog has blanketed much of India's capital city in recent days, severely reducing visibility, restricting traffic and delaying flights in what health officials are calling a public health emergency.
Levels of airborne microscopic particles that are the most damaging to human health reached nearly 1,000 micrograms per cubic meter in the Indian capital on Wednesday, according to U.S. embassy measurements.
The World Health Organization considers anything above 25 micrograms per cubic meter to be unsafe and 100 times its upper limit for long-term exposure.
Heavy smog is not unusual for New Delhi as winter approaches. It is usually caused by burning of crop stubble by farmers in the neighboring states, dust from construction sites, vehicle emissions and burning of coal and garbage, all of which is made worse by seasonal low wind speeds and low temperatures.
"Every possible step required to tackle the situation has been already identified, and the need of the hour is to put them into action," India's Environment Minister Dr. Harsh Vardhan said on Twitter.
"If Government of Delhi thinks that sprinkling of water through helicopter is the most cost effective measure, it's free to do so," he said.
A report in the Lancet medical journal last month said pollution had claimed as many as 2.5 million lives in India in 2015, the highest in the world.
The alarming level of smog has once again underscored Delhi's reputation as one of the worst polluters. The World Health Organization in May 2014 found Delhi to be the most polluted city in the world.