At least 25 people were killed and dozens were trapped after an explosion at a coal mine in Turkey's northern province of Bartin.
Some 110 workers were inside the mine at the time of the explosion. Of these, almost half carried out work at depths of more than 300 metres .
Turkish Health Minister Fahrettin Koca said 11 people had been rescued and were being treated.
As night fell, emergency workers were digging through the rock to try to reach more survivors.
Videos showed miners covered in coal and teary-eyed accompanied by rescuers at the Amasra facility on the Black Sea coast.
Relatives and friends of the disappeared could also be seen in the mine, anxiously awaiting news of their loved ones.
The explosion is believed to have occurred in the depths. Some 49 people were working in a “risky” area between 300 and 350 meters underground, according to Interior Minister Suleyman Soylu.
“There are those who we could not evacuate from that area,” Soylu told reporters.
The cause of the explosion is still unknown. The local prosecutor's office has launched an investigation.
Turkey's energy minister said there are indications the explosion was caused by firedamp , which is methane that forms an explosive mixture in coal mines.
“We are facing a truly unfortunate situation,” he said. There were partial collapses inside the mine , he explained, but there were no fires and the ventilation was working properly.
Turkish President Recep Tayyip Erdogan is expected to visit the site on Saturday. Amasra Mayor Recai Cakir said many of those who survived suffered “serious injuries”.
A worker who managed to escape on his own recounted: “There was dust and smoke and we don't know exactly what happened.”
The mine belongs to Turkish Hard Coal Enterprises, a state-owned company.
Turkey witnessed its deadliest coal mining disaster in 2014, when 301 people died after an explosion in the western city of Soma.