Volkswacht Bodensee - Students ordered to wear masks in smog-hit Lahore

The Punjab state government issued the mandate after the High Court declared a "smog emergency" and asked officials to take steps to help mitigate health problems.

On Wednesday night, private and public schools sent out messages to parents via text and WhatsApp, stating that children must come to school wearing masks for a month.

"Parents whose children suffer from asthma or eye problems often stop sending their children to school. So this is a good step by the government," said Madeeha Hassan, a secondary school teacher in the city.

Student Afshan Maqsood, 15, has had two bouts of throat infections since the beginning of October when the smog arrived.

Wearing a mask is "better than being sick", she said.

Globally, South Asia is the region worst hit by air pollution, according to the Air Quality Life Index report from the University of Chicago.

Pakistan is the fourth most polluted country -- behind Bangladesh, India and Nepal -- in terms of annualized, population-weighted averages of fine particulate matter, which is linked to lung disease, heart disease, strokes and cancer.

Air pollution has worsened in Pakistan in recent years, as a mixture of low-grade diesel fumes, smoke from seasonal crop burn off and colder winter temperatures coalesce into stagnant clouds of smog.

Lahore, the country's second-most populous metropolis and close to the border with India, is consistently ranked in the top 10 cities globally with the worst air quality by monitoring firm IQAir.

On Thursday it was ranked number two, second only to New Delhi.

"We have the dirtiest diesel and fuel in the world," Ahmad Rafay Alam, an environmental lawyer, told AFP, calling smog "a total failure of governance".

L.Stucki--VB