Around 24 people are still missing, as per local disaster relief headquraters.
More than 1,000 rescue workers are carrying out search and rescue work at the site, Xinhua news agency reported.
Preliminary investigation by an expert group determined that the disaster resulted from a collapse in the steep cliff area atop the slope, said Wu Junyao, director of the natural resources and planning bureau of Zhaotong.
The collapsed mass measured nearly 100 metre in width, 60 metre in height, with an average thickness of around 6 metre, he added.
IANS