Eight miners were killed after an earthquake that occurred 1,500 meter below the surface in Poland sent a tremor through KGHM’s Rudna copper mine on Nov. 29.
The tremor was recorded with a magnitude of 3.4 and caused extensive damage to the mine, Europe’s largest copper mine, but the mine remained mostly open, reported the state-run news agency PAP.
The tremor hit the Rudna copper mine at 2009 GMT (3.09 p.m. ET) on Tuesday, KGHM said, causing extensive damage, but the mine remained mostly open.
“The rescue operation lasted for 24 hours. We have done everything to save the miners, unfortunately we lost,” said Rudna mine director Pawel Markowski. He called the tremor KGHM's biggest tragedy in the past 55 years.
The epicenter of the tremor was 1,500 meters below the surface, with a magnitude of 3.4, PAP reported.
Sections of tunnels hundreds of meters below the surface were blocked by rocks, preventing access to the missing miners.
State-run KGHM said the Rudna mine, in operation since 1974, had 11 shafts reaching a depth of 1,244 meters.
"We are all shocked by the scale of this tragedy, which occurred in a place we had assessed as exposed to a moderate level of risk," KGHM Chief Executive Officer Radoslaw Domagalski-Labedzki said.
Domagalski-Labedzki also said nine people working in the mine had suffered spinal and head injuries and five were in hospital. KGHM's spokeswoman said none were in a life-threatening condition.
Tremors often occur in underground mines as removing ore and digging tunnels from beneath the surface weakens the structure of the surrounding rocks. But most tremors are harmless.
Prime Minister Beata Szydlo canceled the government's weekly cabinet meeting and visited the mine late in the afternoon.