Another four miners are still missing from the Rudna copper mine near the town of Polkowice, the "Gazeta Wyborcza" daily reported. 

Pawel Markowski, the managing director at the mine, said a doctor confirmed the death of a miner that rescuers reached on Wednesday morning. The rescuers can also see another of the missing miners but have no contact with him and do not know what condition he is in.

Three miners who were severely injured are currently in stable condition in hospital, according to radio station RMF FM. They suffered backbone and head injuries in the quake, whose epicenter was 89 km (55 miles) from Wroclaw and about 40 km from the eastern German border.

The news service Onet.pl reported (below) that the search for the miners is ongoing. 

The quake struck at 9:09 p.m. (20.09 UTC), according to the US Geological Survey. The quake was shallow - 10 km (6.2 miles) deep - which magnified its effect at the mine.

"That was not a small quake," Markowski said.

Polish Radio says the dead miners were 33 and 47 years old. The mine has called a four days of mourning.

"There were 16 people in the danger zone. Some of them were walked out," Jolanta Piatek, spokeswoman for KGHM - one of the world's largest producers of the copper and silver - told private radio RMF FM.

The Rudna mine:

KGHM has now lost seven miners this year in accidents in its mines.

Poland has been hit by 332 earthquakes so far in 2016, the strongest of them with a magnitude of 5.8.

(dpa, Reuters, AP)