The blast at the mine near Uricani most likely was caused when an accumulation of methane gas detonated, Diana Fullop with the Hunedoara prefecture told Romanian news agency Agerpres.
"Unfortunately, five miners caught [in the] underground mine [at] Uricani lost their lives," Fullop said, adding teams of rescuers were working to bring the miners' bodies to the surface.
Agerpres said the mine has about 800 workers.
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