Two miners were killed and rescuers were struggling to locate three others after an earthquake hit a coal mine in the country's south, the mine's management company said Sunday.
The rescue workers managed to pull two miners up to the surface on Sunday but doctors there pronounced them dead, Daniel Ozon, the CEO of the Jastrzebie Coal Company (JSW) managing the mine, told reporters.
One of the dead men has been identified and the family were being informed, he said. A letter to his wife was found near the man's body.
DNA tests will be carried out Monday to idientify the other victim.
More than 200 miners and rescue workers were still searching for the three missing men, in sweltering heat around a kilometre (0.6 miles) beneath the surface.
"We are doing all we can to find them as quickly as possible," said Ozon.
The earthquake hit the mine at 11:00 am (0900 GMT) on Saturday about 900 metres (3000 feet) below ground level, Anna Swiniarska-Tadla, a spokeswoman for the WUG mining office told PAP news agency.
According to the Polish Mines Office it was a 3.42 magnitude quake.
Around 250 miners had been working underground when the quake struck, according to JWS.
Local residents also reported feeling a strong jolt in their homes in the region not known for seismic activity.
JSW is the largest company producing coking coal in the European Union.
Ozon said that family members of the missing miners were being offered psychological counselling at the mine site.
Poland's Prime Minister Mateusz Morawiecki visited rescued miners in hospital after meeting with mining officials late Saturday.
President Andrzej Duda arrived at the mine Sunday noon as the rescue operation was in full swing.
Coal is the main energy source in Poland with 65.5 million tonnes mined in predominantly state-owned mines the country last year.
Mining accidents have claimed over 200 lives in Poland over the last 45 years, according to statistics compiled by Poland's PAP news agency.
Poland's right-wing government and previous administrations have based their energy policy on plentiful domestic coal and taken little action to invest in or promote renewables to mitigate heavy pollution.
Smog from coal has spiked to record levels nationwide in recent years, with experts estimating there are some 50,000 premature pollution-related deaths per year in the country of 38 million people.
Poland is set to host the UN's COP 24 international conference on climate change late this year.
