Prosecutors are investigating four German police officers after footage emerged showing them attacking a man when he refused to put out a cigarette.
He had been involved in an accident that left a car overturned in a busy street in Stuttgart, causing an estimated €20,000 (£17,000) of damage to property.
As traffic passes by and emergency service workers milled around, police officers can be seen approaching the man, asking him to put out his cigarette.
When he refuses, one officer pushes him backwards, before pulling him down to the ground by his neck.
Two other officers then help restrain him as another officer pulls out a baton and repeatedly strikes the man’s rear.
At the same time, another officer can be seen hitting the man repeatedly in the head before he is pinned face-down under the weight of thee officers.
A summary of the incident originally released by Stuttgart police said a 35-year-old passenger who was injured in the crash had launched an attack in on 19 February.
“A verbal argument led to an assault on the part of a 35-year-old man against a 28-year-old police officer,” it said.
“In the course of the dispute, both of them fell, and the officer hit his head on the pavement.
“He fortunately suffered only minor injuries and was able to leave hospital the following morning.”
The passenger was initially put under investigation over the incident for “resisting police officers” in Willy-Brandt-Strasse.
Police said that the emergence of the footage on social networks has triggered a new investigation by the Stuttgart prosecutor’s office and a separate police misconduct probe.
Two officers involved have already been removed from active duty while the case continues.