Mining executives and personnel were among the 25 initially detained as an investigation into last week’s tragedy was underway.
The detentions came five days after a fire caused deadly carbon monoxide to poison those trapped inside the mine in Soma, Turkey.
The death toll was the country’s worst ever recorded in connection to a mining accident.
It sparked country-wide protests directed at mine operators accused of ignoring safety regulations and the government for its closeness with the mining industry and its insensitive response.
Prime Minister Recep Tayyip Erdogan was accused of assaulting a schoolgirl who called him a murderer, while his aide was photographed kicking another protestor.
Police had to form a cordon around the courthouse in Soma as a crowd of media, onlookers and relatives of those detained grew steadily.
Police are still questioning those thought to be involved.
The last of the 301 victims were buried on Sunday.