Representing workers in a range of industries, the unions are furious over what they say are poor safety standards since the formerly state-run mine in Soma, located about 300 miles (480 km) southwest of Istanbul, was leased to a private firm.
“Hundreds of our worker brothers in Soma have been left to die from the very start by being forced to work in brutal production processes in order to achieve maximum profits,” a statement from the unions said.
“We call on the working class, laborers and friends of laborers to stand up for our brothers in Soma,” it said, urging people to wear black.
As rescuers pulled dead bodies from the site and hopes dimmed for another hundred workers still believed to be trapped inside, anger swept a country which has boasted a decade of rapid economic growth but still suffers from some of the world’s worst workplace safety standards.
Furious residents broke windows at the local government offices in Soma on Wednesday, heckled Prime Minister Tayyip Erdoğan when he visited the site and jostled his entourage. Pockets of protests erupted in Istanbul and the capital Ankara.
The nation’s previous worst accident was in 1992, when a gas blast killed 263 workers in the Black Sea province of Zonguldak.
The rescue operation was hampered late on Wednesday as the fire inside the mine continued, making it extremely hazardous for the rescue crew to retrieve bodies.
Energy Minister Taner Yildiz said the ventilation systems which pumped fresh air into the mine had been relocated and that the teams were getting ready to go back inside.
But more than 40 hours have passed since the fire knocked out power and shut down the ventilation shafts and elevators, and both government officials and rescue workers see little chance of more survivors coming out alive.