The passenger was said to have repeatedly pulled his mask down in order to swig from a vodka bottle.
The bus driver, having asked, then demanded that the drunken passenger put the mask back on, was then assaulted.
The man, according to witnesses, let loose with a volley of insults, then threatened him before finally spitting in his face.
The bus driver got off the bus and informed the police. Meanwhile, the unruly passenger smashed a window on the bus.
As police officers arrived on the scene they were met with abuse and threats of physical violence.
Among other things, the 30-year-old Slovak national, who has no permanent residence in Germany, suggested the officials were racists.
The drunken man then tried to spit on the emergency services personnel, he was brought to the ground, restrained and taken into custody.
A blood sample was taken at the scene by order of the public prosecutor and the man now awaits charging.
