An investigation has been launched at a German potash mine after three workers died from breathing in carbon dioxide.
The incident happened near the town of Unterbreizbach in the east of the country. The men were aged 24, 50 and 56.
Carbon dioxide occurs naturally in potash which is mined using controlled explosions.
Mine owner Rainer Gerling explained what happened:
“After the explosions, we carry out checks to see how much carbon dioxide is in the mine. This was the actual job of these employees, and they were then surprised by the amount of CO2 on the site.”
The area above ground was evacuated when the explosions released a large amount of dust. Initially seven miners were trapped but four were rescued.