Toxic smog which shrouds Lahore poses cross-border challenge in South Asia

Smog enveloping Lahore has caused health problems for its people (KM Chaudary/AP)

The air smells burnt in Lahore, a city in Pakistan’s east that used to be famous for its gardens but has become infamous for its terrible air quality.

Toxic smog has caused ill health among tens of thousands of people in recent months as Lahore sits in an airshed – an area where pollutants from industry, transport and other human activities get trapped because of local weather and topography so they cannot disperse easily.