According to police, the 120-centimeter-tall robot approached the girl outside a street food stall shortly before midnight on Saturday in central Cologne.
Police said the robot allegedly molested the girl, causing her to scream and move away. The assault was filmed and livestreamed publicly on social media on an account with an open comment section.
The robot belongs to a 16-year-old boy who is suspected of operating it alongside a 19-year-old man at the time. Police found the two a block away shortly after the incident. The robot, which was found in a car, has been seized.
