Officials at the Turkish coal mine, where a devastating explosion and fire killed 301 workers last week, are accused of ignoring dangerously high levels of toxic gas registered by sensors inside the mine days before the disaster.

Prosecutors and inspectors probing the incident have reportedly obtained data from the mine, indicating that sensors registered high toxic-gas levels inside the mine two days before the May 13 accident, which is believed to be the worst mining disaster in Turkey's history, local media reports said, adding that company officials did not keep a record of toxicity inside the mine, which is now a crime scene.

According to prosecutors, two more people have been arrested for the deadly incident in the western town of Soma, raising the total number of arrests to five. The arrested officials, including executives and supervisors at mine owner Soma Komur Isletmeleri A.S., will face charges of negligent death in relation to the accident, Associated Press, or AP, reported, citing Turkish news reports Tuesday.

Authorities initially detained 25 people as part of the probe, but several were released without charges filed against them while eight were released but could be summoned in the future for further interrogations. Many others, including Can Gurkan, the company's CEO, are still being questioned by authorities, the state-run Anadolu Agency reported.

Miners who survived the disaster also told AP that the company’s supervisors ignored rising gas levels and failed to take adequate measures, but government and mining officials have said that negligence could not be a factor in the fire as the mine was inspected regularly and that safety standards were high.