Air pollution in Hong Kong has hit a record level. The quantity of harmful substances in the air is almost double the amount at which people are advised to stay indoors.

The region's pollution has been boosted by a massive sandstorm travelling south from China. However, the sandstorm has only added to the city's poor air quality, which often leaves its world-famous skyline cloaked in a thick haze. This is due mainly to the volume of car traffic in the streets, to the boats traversing its harbour, and to the thousands of factories in southern China emitting pollutants.

Pollution in nearby Taiwan also hit record levels on Sunday, shrouding the island and forcing authorities to urge residents to stay indoors on Monday.