Andrzej Grygiel/PAP

An underground tremor with a magnitude of 2.6 rocked residents of the southern city of Katowice and the surrounding area on Sunday evening.

The quake, which struck near the area of the Staszic coal mine caused no disruption underground, according to information provided by representatives of the Polish Mining Group (PGG), the mine’s owner.

PGG spokesman Tomasz Glogowski told PAP that the tremor occurred on Sunday after 9pm.

“No one was hurt underground. There are no effects of the quake down below. The mine is operating normally,” he said.

“There were no reports from the surface, but the shock was felt very strongly in Katowice and the surrounding area,” he added.

The most common cause of quakes is the release of energy accumulated in the rock mass. Due to different geological conditions, some tremors are felt strongly on the surface but most do not pose a direct threat to miners and residents of mining areas.

Those that cause damage to infrastructure underground or on the surface are called rock bursts.

In the years 2018-22, 19 rock bursts hit Polish mining, resulting in 23 fatal, three serious and 98 minor accidents.