By 6 a.m. on Saturday, firemen had received 3,700 emergency calls, mostly from northern Poland, Karol Kierzowski said on Saturday morning.
"We had 3,582 events reported in the north," Kierzowski said, but added that the fire brigade received calls from all over Poland.
In northern Poland, a tree fell on a car with five people inside, including two children.
"All of them were freed by firemen and handed over to emergency medical services," the spokesman said.
Two house roofs caught fire in the storm and 20 tent camps had to be evacuated.
The storms moved across Poland from the west to the east. (PAP)