'Had they got to me an hour later I would have been dead'

The sky seemed to darken, and a rumbling sound unlike anything Ma had ever heard before quickly grew louder and louder. Within seconds she was buried under the rubble of her newly built three-story home in Yingxiu, Wenchuan county.

Two huge slabs of concrete lay on her chest, and as the earth continued to shake in the minutes and hours that followed the rocks seemed to press down ever harder on her.

"My breathing became more difficult and faster," she says. "My body was numb. I felt no pain, and I had no strength to cry out."