The strike occurred in the Liberec-Vratislavice castle park about 90 kilometres (55 miles) northeast of the capital Prague on Sunday afternoon.

"As far as I know, the lightning injured five children and eight adults," Vaclav Ricar, spokesman for the Liberec hospital, told AFP.

"I was told that of the eight adults, five had to undergo resuscitation," he said, adding that the injured were on their way to the hospital.

Local firefighters said on X that the lightning "struck a tree under which there were people".

"We are assisting emergency services with the transport of the injured and providing pre-medical care," they added.

Police said on X meanwhile that the lightning had injured 15 people.

The Czech Republic was hit by heavy rain on Saturday and storms on Sunday.

Heavy rain also caused floods in neighbouring Germany over the weekend, with one volunteer firefighter reported dead and another missing on Sunday.