Tibet quake: Cold enemy of survivors

RESCUERS SCRAMBLE | Experts say those trapped under rubble or shelterless for over 24 hrs will die of hypothermia in five to 10 hours even if uninjured as temperature drops to 18 degrees Celsius

Twenty-four hours after the temblor struck, rescuers were looking for survivors in an area roughly the size of Cambodia as those trapped under rubble would have endured a night in sub-zero temperatures. So far more than 400 people have been rescued, Chinese officials said on Wednesday. However, an unknown number is still unaccounted for in freezing weather.

The epicentre of Tuesday's magnitude 6.8 quake, one of the region's most powerful tremors in recent years, was located in Tingri, about 80 km north of Mount Everest, the world's highest mountain. It also shook buildings in neighbouring Nepal, Bhutan and India.

Temperatures in the high-altitude region dropped as low as minus 18 degrees Celsius (0 degrees Fahrenheit) overnight. People trapped or those without shelter are at risk of rapid hypothermia and may only be able to live for five to 10 hours even if uninjured, experts say.