A Munich resident, Tom Roth, uploaded the video to his Facebook page, saying the fight broke out after one of the asylum seekers was rejected by a woman who he had placed his hand upon on the train, The Daily Mail reported.
In response, the man smashed his hand against the carriage's glass window - an aggressive act of defiance the train's other passengers requested he desist.
"There were about 10-15 people beside and behind me. The situation was brought under control. When the train reached the station I called the police. They said there was nothing they could do," the witness wrote.
The incident is the latest violent coming together of asylum seekers and Germans to have come to light in recent weeks.
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