Lightning strikes kill five people, including two children, and injure more than 100 in Poland

Polish rescue workers move an injured tourist into a helicopter near Zakopane, Poland after a sudden lightning storm killed five people, including two children.  AFP / Piotr KORCZAK

Lightning struck across the Tatra Mountains in southern Poland and neighbouring Slovakia on Thursday, killing five people and injuring more than 100 others in an area popular with hikers and families.

Witnesses said the thunderstorm came suddenly on a day that began with clear weather.

The lightning struck Poland's Giewont peak, a trekking destination 1,894 metres above the ground, and other locations across the Tatras.

Four people including two children were killed on the Polish side, Kinga Czerwinska, a spokeswoman for the Polish air ambulance service, told broadcaster TVN24.

The Slovak rescue service said a Czech tourist fell hundreds of metres and died after lightning knocked him off Banikov's peak.

Rescuers with the Polish Tatra emergency service said they believed the lightning probably hit some of the metal chains installed on Giewont to aid tourists in their climb.

Some of the injured were taken by helicopter to a hospital in the Polish mountain resort of Zakopane.

Krakow province governor Piotr Cwik said that the death toll could rise.

Prime Minister Mateusz Morawiecki, who went to Zakopane, said some among the over 100 injured were in very serious condition with severe burns or head injuries, as they fell after the lightning strikes or were hit by falling rocks.

Mr Morawiecki extended his sympathies to their relatives.

The Tatras, part of the Carpathian mountain range, are the highest mountains in Poland and in Slovakia and attract tourists from near and far with scenic lakes and peaks that rise to 2,655 metres.

Thursday's lightning strikes were the worst accident in the Tatras since August 1937, when lighting killed four people on Giewont.

Footage showed rescuers racing to a helicopter to get to the peak in rainy, foggy weather, and a helicopter landing at the hospital in Zakopane with injured people.

Rescue workers on Friday plan to keep checking the mountains for anyone who might need help.

Tourist Grzegorz Pyzel said he was halfway up Giewont with his wife in clear weather when suddenly they heard thunder. They thought it was a jet overhead.

"But soon lightning struck and we turned back," Mr Pyzel said. "Suddenly it started pouring and you could hear thunder roaring from every possible direction."

The couple reached a shelter on Hala Kondratowa at the foot of the mountain, and soon others arrived saying there were injured people further up the mountain, he said.

In another rescue operation in the Tatra Mountains, emergency workers have been searching for two cavers who went missing on Saturday after being trapped by rising water.

Rescuers were using small amounts of explosives to widen passages in uncharted parts of the Wielka Sniezna cave, Poland's deepest and longest, to look for them.