The Toronto police marine unit is reminding people to be cautious near waterways because of unstable ice.

Members of the unit issued the warning Tuesday as they practised their ice-rescue drills in the icy waters of Lake Ontario near the Leslie Street spit.

Police say the majority of ice rescues involve dogs and officers do not want people to attempt rescuing their pets on their own.  

"If your dog is having trouble give us a call. We have the equipment. We'll get out there and get your dog. Dogs are pretty good, they can last for a while out there, we cannot," said Const. Patrick McLeod of Toronto police's marine unit. 

Toronto police say sitting in the water for 10 to 15 minutes could cause someone to lose the use of their arms and legs, which will lead to sinking. 

"It is a very mild winter this year, so it's actually more dangerous. The ice is quite unstable," said McLeod.  

"We basically think all ice is unsafe, so we encourage you to stay off the ice."