The suspicion of a passer-by in Brandenburg an der Havel, east Germany, was first aroused when she saw a Honda moving in fits and starts along the edge of the road.
The erratic vehicle finally crashed into a parked car and pushed it into a third.
She approached the Honda and was astonished to find a six-year-old girl looking back at her from behind the wheel and a seven-year-old friend next to her, police said.
After removing the two children from the car and making sure the keys were well out of reach, the witness called the police.
The officers found that the girl and her seven-year-old passenger had decided to go to the shops after the girl's parents went to work, leaving the pair alone.
They had simply plucked the car keys from the hook on the way out of the apartment.
Both children were unhurt in the accident, but they ended up causing €4,500 worth of damage.
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