A single coal mine in Poland's Upper Silesia region is behind a record spike in the country's confirmed coronavirus cases, the health ministry says.

Over the weekend 1,151 new infections were recorded nationally.

An outbreak among miners and their families at the Zofiowka colliery in southern Poland accounted for two-thirds of that figure...

Upper Silesia is Poland's industrial heartland with more than a dozen active mines where workers toil in humid conditions at close quarters.

More than 4,000 people in the region have tested positive for the virus. Of Sunday's new infections, 57% were recorded in Upper Silesia.

Coal company JSW says it has reduced output at a mine in Pniowek, and PGG, another company, closed some mines temporarily in May, reports Reuters...

The spread of infection in confined workplaces has also been seen in mines and factories in South Africa and the US...