Aziz Ahmed, a local schoolteacher in Buner, northwestern Pakistan, said the thunder accompanying recent torrential rains was so loud he thought the "end of the world had come."

Water, rocks and trees were swept down the mountainside after two days of intense monsoon rains, burying people and homes in their path.

"You can say that those who survived have gone mad,” said Ahmed, pointing to a house where just one family member still lived.