TOKYO - A gas leak occurred at a major oil processing facility located in the coastal area of Sakai city, Osaka on Saturday morning, leaving one dead and two others hospitalized, local media reported.

The incident was reported around 10 am local time, when emergency services received a call stating that a gas leak occurred in the piping system at the ENEOS Sakai Refinery and that workers had collapsed on-site, national broadcaster NHK reported.

According to local authorities, three male workers were exposed to the leaked gas and were transported to the hospital. One of them was later confirmed dead.

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Initial reports suggest that the leaked substance may have been hydrogen sulfide, a toxic gas. ENEOS is currently investigating the cause of the leak.

The refinery, covering approximately 770,000 square meters, is situated along the coast and specializes in oil refining.