Huge sandstorm hits northern China

Commuters brave the sandstorm as they wait for their bus at a bus-stop along a Beijing street

BEIJING, China -- A massive sandstorm has enveloped most of northern China, covering the capital Beijing in a shroud of dense dust and reducing visibility to less than 50 meters in some areas.

The storm is the strongest and most intense this spring, the official state-run Xinhua news agency reported, and hit China's north on Tuesday with fierce winds.

Sandstorms are frequent in spring, triggered by sudden seasonal temperature changes, Xinhua news agency reported.

Sand is picked up from the expanding desert regions in northwestern China and Inner Mongolia.

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Land and air transportation has been affected in the storm-hit regions which spread from the west to east of northern China.

Visibility had been reduced to less than 50 meters in some areas of the Gansu and Ningxia provinces as well as the Inner Mongolia Autonomous Region, Xinhua reported.

The Chinese government has pledged almost $7 billion to curb a worsening desertification problem and lessen sandstorms.

Desert areas are creeping steadily towards Beijing and risk clouding the 2008 Olympic Games to be hosted by the capital city.