According to the same source, the child was abandoned in a service area in Lisbon and is now in the custody of PSP.
The GNR source also indicated that the car had not yet been found and that the perpetrator "is on the run".
The theft of the vehicle took place near a restaurant, where the car was parked, while "the child's mother went to the establishment to pick up a meal", having "left the car on with the key in the ignition", explained the GNR source.
"GNR immediately took steps to locate the car," he said.
The investigation of the theft was passed on to the Judiciary Police.