Five workers were pulled out of a tunnel on Friday after being trapped for 25 hours by an avalanche that killed at least four in northwest China.

However, 12 others buried in snow drifts of more than 50 meters deep blocking the entrance of the tunnel construction site in northern Xinjiang Uygur Autonomous Region remained missing.

The avalanche occurred at around 10 a.m. Thursday when five workers were in the tunnel and a team were about one kilometer away on their way to the project in the Kazak Autonomous Prefecture of Ili.

The five workers dug a narrow passage through the thick snow over the past day, enabling rescuers outside to get them out.

They were under emergency treatment in a local hospital. Doctors said the five were weak, but not in critical situation.

However, the chance for the survival of the 12 trapped was slim, as more than one million cubic meters of snow piled up at the project entrance made the searching and digging operation very difficult, said Zhang Yun, the prefecture's deputy Party chief.

Eight huge excavators were still digging on the site of the accident.

The tunnel is at a remote area known as "Guozigou". It is about 500 kilometers from Urumqi, the regional capital.

The contractor of the 3.8-kilometer tunnel, part of a cross-border pipeline project to send gas from Turkmenistan to Shanghai, had dug only 260 meters of the tunnel when the accident happened.

(Xinhua News Agency March 14, 2008)