A violent earthquake, with a magnitude of 7.9, shook Asia from Beijing to Bangkok on Monday. China was the most severely hit, with the epicenter located in the Wenchuan region, in the southwestern province of Sichuan. China has mobilised over 50,000 soldiers to the affected regions to help with disaster relief.

The death toll rose steadily throughout Monday. At 1pm (GMT+2), there were 107 known dead. By 2am (GMT+2) on Tuesday, the Chinese authorities reported 10,000 dead. The figure topped 12,000 Tuesday afternoon. Furthermore, 18,645 people are reportedly trapped in the rubble in the town of Miangyang, near the epicentre of the quake.

The first substantial relief team - an army contingent of 1,300 medical staff and troops - reached the devastated Wenchuan county on Tuesday, negotiating the rugged Sichuan terrain on foot. They immediately set up search teams and began treating the injured.

“It was as if the floor was coming away from underneath our feet,” says Henry Morton, one of FRANCE 24’s two correspondents in Beijing. “We’re some 1,500 kilometers away from the epicenter. That gives you an idea of the magnitude that must have been felt in the Sichuan province itself.”

The Gansu and Yunnan provinces, as well as Chongqing, a region of 30 million people, have also felt the tremors.

Arriving in Sichuan, Prime Minister Wen Jiabao called the quake a “disaster” and urged the population to stay “calm” in a televised interview.

A race against time

According to the official Chinese press agency, more than 7,000 people lost their lives in the Beichuan district alone, where 80% of buildings were flattened. Overall, an estimated 10,000 people were injured in the area, making it one in ten inhabitants.

The city of Dujiangyan has suffered widespread devastation. At least 850 students are buried in the rubbles of a local high school, while fifty are already dead. Hundreds of employees are also missing after their hospital collapsed.

In the nearby city of Shifang, two badly damaged chemical plants have been leaking some 80 tons of liquid ammoniac.

“The province has been difficult to reach because Chengdu airport, the closest to the epicenter, has been closed and should remain so tomorrow,” explains FRANCE 24’s Sébastien le Belzic. Sichuan is a mountainous region. Land slides and damage to roads and phone lines are hindering the progress of rescue teams, while also making it difficult to get news from the front.

Bad weather has also slowed down relief efforts. "It has been raining for three or four hours now," said FRANCE 24's correspondent in Chengdu Henry Morton on Tuesday at 2pm (GMT+2). "That is going to seriously hamper rescue efforts for today."

Some three thousand soldiers and rescue teams are on their way to the region, according to le Belzic. Sichuan is close to Tibet, where the many Chinese garrisons can easily be mobilized.

China is regularly hit by earthquakes. One of the worst ones devastated Tangshan, in north eastern China, in 1976, claiming more than 200,000 lives. Western experts say today’s earthquake could leave as many as 700,000 dead.