France, Aug. 21 -- The village of Nyos, in north-west Cameroon, was a peaceful place. On that day, its people carried out their work as usual - some in the fields, others leading cattle out to pasture.

The village was also home to a gaping hole almost 210 metres deep, at an altitude of 1,091 metres - an old volcanic crater filled with stagnant water. Locals were proud of the site, which was listed as one of the region's must-see tourist attractions.

No one suspected that tragedy was about to visit this small community as they went to bed that night. 'A blanket of silence'

Sometime between 9pm and 10pm that evening, witnesses reported hearing a noise like a landslide. Scientists believe it was most likely a minor earthquake - identified...