Four out of 29 miners working at the site climbed to safety after the accident took place at 7:56 am Friday, local news portal sd.dzwww.com reported. The location of six miners stuck underground has been confirmed and a rescue operation is underway while 19 remain missing, said the news portal.
Authorities have rushed about 90 firemen to the scene. It is not clear if there are casualties.
The impact of the collapse was as strong as a magnitude 4 earthquake with a depth of 10 kilometers, according to Xinhua.
Currently local railway authorities are checking the safety of railway lines and four trains are running late.
