A public health emergency was declared as choking smog blanketed New Delhi on Tuesday, with authorities ordering the temporary closure of all primary schools in the world's most polluted capital city.
New Delhi experiences suffocating smog every year around Diwali, when farmers in north India burn the stubble left behind after the harvest and revellers let off smoke-spewing firecrackers.
Heavy smog that blanketed parts of China at the weekend cleared somewhat on Monday, but it was likely only to be a brief respite with more choking smog expected to return within 24 hours.
China's smoggiest city closed schools on Wednesday as much of the country suffered its sixth day under an oppressive haze, sparking public anger about the slow response to the threat to children's health.
Beijing city government has issued a red alert for severely high levels of air pollution in the city for three days from December 17 to 21, according to a post on the Beijing environmental protection bureau's official Weibo account.
Delhi's government announced Friday that it will install air purifiers and a mist-making device at major road intersections in the Indian capital to curb choking levels of pollution.