BARRIE, ONT. -- There were some tense moments on Lake Simcoe Saturday as three vehicles broke through the ice on Cook's Bay.

No one was injured as the vehicles sank into about four feet of frigid water. A tow truck pulled the vehicles out while scores of people watched on.

It's a reminder of how uneven and unreliable ice on Lake Simcoe remains despite this week's deep freeze.

Even after repeated warnings from police and ice hut operators, about a dozen people parked on the lake Saturday morning.

"Do not park on the ice, do not drive on the ice, it's not safe yet," says Jack Hayward, producer of the Blue Ice Report.

Ice hut operator and a tow truck driver Rob Crosbie fished vehicles out of the water. While the process took hours, he says the drivers were lucky the water wasn't deep.

Donny Crowder with Hot Box Huts says the ice is as thin as two inches in some spots.

"It's really quite risky out in the bay guys, we're not quite ready here just yet," Crowder says.

Ice hut operators are pleading with people unfamiliar with Lake Simcoe to ask them about conditions before venturing out.