The incident started after the 21-year-old hospital orderly from Guinea hopped onto a train at the last second and held the door open for his girlfriend.
The 51-year-old train driver then switched on the train’s PA system and racially abused the man as a “Neger” – which ranges in meaning between “nigger” and “negro” in German.
“Everybody could hear it,” said a police spokesman.
The upset passenger promptly knocked on the driver’s cabin to complain, but the driver ignored him.
At the next station, the passenger stepped out of the train to photograph the driver with his mobile phone, at which point the driver opened the door and kicked the man to stop him. The mobile phone fell to ground and broke.
The train driver now faces charges of slander, property damage and assault.
Several passengers in the full S-Bahn were appalled by the train driver’s behaviour, according to a statement by the federal police. Two witnesses accompanied the orderly to the police station at Muinch’s main train station to complain.
The driver reported the incident to the S-Bahn control centre and admitted he had used the epithet and kicked the man. But he said he had felt threatened by the passenger’s aggressive knocking on the door to his cabin.