Rescue workers are still searching for two workers who were trapped after a coal mine collapsed near the town of Simitli in southwestern Bulgaria on Tuesday.
Two of the four coal miners who had been trapped underneath 50 meters of land mass were confirmed dead Tuesday.
Rescue teams have searched for their two colleagues throughout the night, local media inform.
The collapse happened around 9:30 am Tuesday.
It is the fourth major accident in the Oranovo mine in the past eight years. Union leaders said the reason for the collapse was poor safety standards.