A devastating earthquake in China has killed over 12,000 people.

The widespread destruction has left many without water or power, and thousands are still trapped under the rubble.

A man hiding under his desk, the building shaking around him, this was the moment the earthquake struck.

Within seconds people were running for their lives - at least the lucky ones were.

In an instant, the quake shattered an enormous swath of southwestern China.

In one county alone, there are up to 5,000 dead.

Outside the city of Chengdu, a high school collapsed on top of 900 students, trapping them under tons of rubble.

China's Prime Minister responded unusually fast.

"Hang on, the Army is on its way to rescue you."

The walking wounded filled the streets, along with those who couldn't walk.

Makeshift hospitals were set up on the spot outside, as more than 300 aftershocks rocked this region.

"When we got there, there were like thousands of people standing in the street and they were really got scared," stated Summer Jiang, an Operation Blessing Humanitarian.

"And all the people were still wearing their underwear and didn't wear any shoes."

By nightfall nearly 20,000 soldiers were on the ground setting up portable aid centers in tents, as frightened residents chose to sleep outdoors-too jittery to return home.

Now, the race is on to rescue those buried alive, trapped beneath piles of rubble that used to be their homes, hospitals and schools.

And this isn't the worst of it, either.

The hardest areas remain out of reach, cut off by roads blocked by tons of debris.

The state media has reported 313 aftershocks so far.