MIDDLETON, Wis. -

An ice fisherman learned about the danger of pressure cracks while driving his four-wheeler on the ice Monday morning.

Dane County sheriff's deputies responded to a report of a four-wheeler stuck on the ice just before 7 a.m. Monday.

When officers arrived, they found the back end of a four-wheeler in the water after it fell in on a pressure crack in the ice.

No one was hurt, but the ice fisherman will need to have a friend tow the vehicle off the ice.

Deputies warn ice fishermen to be aware of pressure cracks as they go out on the ice this winter.

“It’s constantly getting thicker and constantly getting thinner. You have areas where you have current, you have natural springs -- all of those work to erode the ice. By its very nature, you can’t tell how much ice you’re actually on until you drill a hole and look,” Dane County Deputy Sheriff Mica Weber said.