Three people arrested in Turkey by police investigating the Soma mine disaster are facing a charge of causing multiple deaths, officials say.
They were among 25 people detained on Sunday, including several mining company officials.
The explosion and fire on Tuesday sent carbon monoxide gas into the mine's tunnels, claiming 301 lives.
It was the country's worst-ever mining disaster and sparked protests against the government and mine operators.
"The crime of which the suspects are accused is causing multiple deaths and injuries due to negligence," public prosecutor Bekir Sahiner told journalists.
Six of those arrested on Sunday have now been released, he added.
The prosecutor did not identify the three suspects facing charges.
Turkey's Dogan news agency said mining company Soma Holding's general manager Ramazan Dogru and operations manager Akin Celik were among the 25 arrested.
It is not yet clear if either of the men faces charges. Soma Holding insists the disaster was not caused by negligence.
Muzaffer Yildirim, a miner whose brother died in Tuesday's incident, told the BBC the managers were responsible for the disaster and "should be punished".
Initial reports suggest that the disaster could have been caused by coal in the mine overheating.
Rescue operations ended on Saturday after the bodies of the last missing workers were recovered.
The government has faced growing anger from the public, with protests in the western city of Izmir, Istanbul and Ankara.
In Soma, local authorities have banned demonstrations. Dozens of people were detained as they attempted to travel there on Saturday to offer condolences.
Prime Minister Recep Tayyip Erdogan has been criticised for appearing insensitive in his reaction to the disaster.
Both Mr Erdogan and his aide Yusuf Yerkel have come under pressure after photos appearing to show them assaulting protesters were published in Turkish media.