A coal mine accident in Mexico's Coahuila killed six miners who were trapped under 100 tons of coal and rock on Friday.
The collapse happened near El Progreso mine, where seven family members died in a methane explosion, BBC News reported. One miner was rescued alive earlier Friday from that explosion, the Associated Press reported.
Almost 300 miners evacuated the mine safely, Reuters reported.
The men were reportedly crushed by falling coal, Federico Mendez Pacheco, representative of the Coahuila state civil defense office in the coal-mining region, told Al Jazeera.
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The two accidents have shed light on the dangerous conditions of the small, mostly unregulated "pozito" mines, Al Jazeera pointed out. Men have been mining the pozitos in Coahuila for over 100 years.
30 people died in accidents in Coahuila's coal mines in 2011, according to the Relatives of Pasta Concho, a group founded by mining victims' family members. The organization told the BBC the there are at least 50,000 people working in Coahuila's coal mines.
State Public Safety Secretary Jorge Luis Moran Delgado said an investigation will now be launched "to determine the causes of this fatal accident," Fox News reported.
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