Forty persons died in an explosion at a coal mine in Turkey’s northern Bartin province, Reuters reported on Saturday. The explosion took place at the Turkish Hard Coal Enterprises on Friday when 110 miners were at work – half of them were at a depth of 300 metres, reported the BBC.

Turkey’s Interior Minister Suleyman Soylu said on Saturday, that 58 of the 110 miners were rescued by the teams or got out by themselves, reported Reuters. The search and rescue team are still looking for one missing miner.

“There is still a fire going on there, miners and teams have made great sacrifices not to leave their brothers there,” Soylu said, reported Reuters.

Turkey’s Energy Minister Fatih Donmez said that initial assessments of the explosion suggest that it was likely caused by firedamp, which is when methane forms a flammable mixture, reported the Associated Press.

Turkish President Recep Tayyip Erdogan said on Saturday that the country’s judicial authorities will investigate the cause behind the explosion. “Our judicial authorities will investigate this tragic incident, which hurt our lives and lungs, in all its dimensions, and will not leave even the slightest negligence unanswered,” Erdogan tweeted.

Turkey’s neighbouring country Greece has also offered assistance in rescuing the miners. Greek Prime Minister Kyriakos Mitsotakis said on Saturday that he is ready to send assistance immediately to help in the search for survivors.