BEIJING (AFP) - A towering wall of sand rushed over factories and apartment blocks in north-western China's Gansu province as seasonal sandstorms barrelled across the country, causing air pollution and traffic accidents.

Aerial images as it struck showed an apocalyptic scene as a billowing cloud of yellow dust smothered Gansu's Linze county on Sunday (April 25).

State media CCTV reported multiple car accidents in the province caused by low visibility, while meteorologists have warned people to stay indoors and keep windows shut with more storms expected across northern China on Tuesday.

China suffers from enormous dust storms each spring that lift sand from the Gobi desert and dump it onto cities as far away as Shandong on the eastern coast.

A sandstorm that pushed air pollution levels off the charts hit Beijing in March, turning the sky a dark yellow and forcing airlines to cancel hundreds of flights.

It was the worst sandstorm in a decade to hit the capital, which has pinned hopes of rebuilding a natural barrier to such phenomena on intensive tree replanting in stripped forest areas, also known as the "green great wall".

Beijing said last year it expected fewer and weaker sandstorms to hit northern China due to the reforestation efforts.