The incident occurred Monday at Chesnay, in the Yvelines.
A nanny was crossing the street with the 3 year old child, which she had the charge, when they were knocked down by a car.
The driver, aged 85 years, came to grill a fire red.
The boy was thrown several metres. By chance, he and his nanny get away with minor injuries.
As to the octogenarian, it is not reported of the accident, and continued its route as if nothing had happened.
A witness followed him, allowing the police to locate and arrest him.
The retiree has been placed in police custody. In the night, a physician has stated that his state of health was incompatible with the procedure.
Therefore, it has been released. It will be convened at a later time.