At least four people have been killed and four others gone missing following a quake that jolted a copper mine in Poland.
Rescuers have retrieved the bodies of four miners at a depth of about 1,100 meters in Rudna mine, which is operated by KGHM company, in the southwestern town of Polkowice, the KGHM head, Pawel Markowski, said on Wednesday.
According to the US Geological Survey, a 4.4-magnitude quake hit deep underground on Tuesday evening near the southwestern town of Glogow. The mine's directors estimated the energy released by the tremor at eight points on a scale of 10 used by the mining industry.
Markowski said the four missing miners were likely buried "a dozen or so meters away" from the rescuers, adding that blocked underground tunnels slowed down the rescue operation.
The KGHM head said five other workers had also suffered minor injuries in the incident. Two of them were hospitalized but doctors said their condition was not serious and they would be discharged within days.
Rudna, which is one of the largest copper mines in the world, operates 11 shafts at a depth of nearly one kilometer.
It has 4,400 employees and extracts about 12 million tonnes of minerals annually.
Prime Minister Beata Szydlo annulled a cabinet meeting planned for early Wednesday in order to visit the mine.