(Xinhua)
Updated: 2008-03-17 08:01

Heavy snowfalls, strong winds, mechanical vibrations and a rapid rise in temperature caused an avalanche that killed at least four and left a dozen missing in Northwest China's Xinjiang Uygur autonomous region, a meteorologist said on Saturday.

Army men clear the snow to search for victims after an avalanche caused by heavy snow in Guozigou area of Northwest China's Xinjiang Uygur autonomous region March 16, 2008. Four have been confirmed dead and 12 are still missing. [Xinhua]

Three heavy snowfalls between March 6 and 12 hit the Guozigou area, undermining conditions at a gas pipeline construction site where the tragedy took place.

Strong winds up to 72 kph at an altitude of 3,000 m had increased the risk of avalanche, said Gao Minghua, the observatory head at the Kazak autonomous prefecture of Yili.

Mechanical vibrations from machines in the tunnel construction site in such bad weather had destabilized the mountain.

This, together with a rapid temperature rise that quickly thawed ice to add weight to the snow, caused the avalanche around 10 am on Thursday, according to Gao.

Twenty-two workers were at the site at the time.

One immediately escaped.

One more body was discovered at 2:25 am yesterday in a destroyed machine room near the tunnel.

Rescuers have thus far recovered four bodies and saved five survivors.

The workers are from the Xinjiang Zhanyou Tianyuan Machinery and Engineering Company, a firm building a 3.8-km-long cross-border subterranean pipeline to send gas from Turkmenistan to Shanghai. The tunnel is about 500 km from Urumqi, capital of Xinjiang.

Fresh snow slides yesterday, which cut off the only path into the tunnel, dimmed hopes for the 12 missing workers, said Yan Cheng, a police official in charge of the rescue.