Relatives of a victim of the mine accident stand next to the grave of their loved one, in Soma, Turkey, Saturday, May 17, 2014.
Police have arrested 18 people, including mining company executives, following the deadly accident that killed 301 miners in western Turkey, according to local media.
The Dogan News Agency reported that Ramazan Dogru, general manager of the mine owned by Soma Holding, and its operations manager Akin Celik, were among those detained Sunday, according to multiple reports. Prosecutors were questioning five people at a local courthouse near the site of the disaster.
Approximately 787 miners were inside a coal mine when an explosion and fire occurred last week. The mine is located in Soma, a town in the province of Manisa, around 155 miles south of Istanbul. Most of the victims died from carbon-monoxide poisoning, with some miners 1,378 feet deep inside the mine.
A Soma Holding representative claims an "unexplained build-up of heat" caused the mine's collapse, according to the BBC. Government and company officials said the accident was not due to negligence, and that the mine was regularly inspected.
"There is no negligence," operations manager Celik said at a press conference Friday, according to the Associated Press. "I have been doing this job for 20 years, but I have never seen anything like this. We would not want harm to come to a single fingernail of our workers."
Celik added that smoke from the underground fie killed many miner who did not have gas masks. Soma Holding representatives said safety standards were high, and that the mine had 50 gas sensors, the AP reported.
Government officials committed to investigating the accident, following widespread demonstrations across Turkey. Some protesters condemned Turkish Prime Minister Recep Tayyip Erdogan for what was perceived to be his insensitive response to the accident; others criticized the government for being complicit in the miners' deaths, blaming it for lax safety standards.
Rescue workers ended the search for survivors Saturday morning, after recovering the bodies of the last two missing miners.
The accident in Soma is the worst mining disaster in Turkey's history. Previously, the country's worst disaster was a 1992 gas explosion that killed 263 workers near Zonguldak, a port city on the Black Sea.