(CNN) -- For as long as eight hours, the small girl hid, unnoticed, in a car with the bodies of two British women and a man shot dead in foothills of the Alps in eastern France.
Probably paralyzed by fear, the 4-year-old remained among the corpses as investigators waited for crime scene technicians to arrive so the car could be opened.
She is now under police protection, as is an older girl, thought to be 7 or 8 years old, who was found injured near the car. She suffered a fractured skull and an apparent bullet wound to the shoulder.
Prosecutor Eric Maillaud told reporters Thursday that investigators failed to notice the younger girl because she didn't move for hours as they waited for the forensic experts.
She was hidden under baggage and the legs of one of the dead women in the car's back seat. A thermal imaging camera failed to pick up her presence, Maillaud said.
The child was "probably terrorized, completely concealed, completely immobile amid the corpses," he said.
Authorities have not identified the three Britons found dead on Wednesday in the car near Lake Annecy, a popular tourist spot in the Haute-Savoie area of eastern France. A fourth victim, a French cyclist found shot in the head near the car, has been named as Sylvain Mollier.
"The scene is dramatic, it's unusual -- it goes well beyond TV fiction," he said.
Multiple bullet casings had surrounded the BMW when authorities came upon it, with bullet holes peppering its windows but none in the body of the car, according to the prosecutor.more