According to Mining News Pro - The quake with a magnitude of 2.66 was felt on Monday afternoon in the Staszic coal mine in the town of Katowice, the heart of Poland’s coal region.

Nine miners were present in the area when the incident occurred, PGG spokesman Tomasz Glogowski said. Six others were taken to hospital after the incident, he said without giving further details.

“The third person is dead,” Glogowski said, revising the toll from the incident up to three from two dead previously.

The tremor has not had significant impact on the mine’s production, the spokesman said.

Poland still generates most of its electricity from burning coal, but coal production has fallen in the past years due to lower investment and efforts to cost cuts.

Last year 21 miners died in mining industry accidents in Poland, official statistics show.