Montreal police are investigating after a seven-month-old baby boy was found locked in a car in the parking lot of the Rockland Centre in the Town of Mount Royal.

Police said witnesses in the parking lot of the shopping centre called 911 after they saw a baby crying inside the locked vehicle.

"An officer who was just around the area came rapidly and saw the baby, who was all wet and he was crying," said Montreal Police spokesman Danny Richer.

Police said it took about 10 minutes to find the baby's mother, who was inside a store. They paged her on the shopping centre's intercom system.

Officers spent Thursday afternoon questioning witnesses to try to find out how long the child may have been in the car.

"Investigators do think it might be 20 to 30 minutes, but they have to evaluate some evidence as far as the security cameras. Some witnesses also parked their vehicles near that vehicle," Richer said.

The child was taken to hospital to be examined.

Police have not said whether the mother, 29, will face charges.

Police are reminding parents to never leave their children unattended.

"It’s always a bad idea to leave children inside the car, whether or not it’s for one, two or three minutes. Always take your kids with you," said Richer.