I witnessed something similar in mid-May this year on an ICE train between Nürnberg and München.<p>As is normal, everyone's train ticket was checked (including mine), but when they came to a group of Chinese tourists, there was a problem with one passenger - he'd pre-purchased 3 months prior with a credit card, but the credit card had since been stolen during their international trip. In Germany, Deutsche Bahn require you to present the exact credit card used to purchase your ticket as identification when asked.<p>The ticket inspector didn't believe the passenger, saying "If your card really was stolen, your replacement card will be the same number" and "If your credit card was stolen you would go to the police to report it." I spoke up at this point in support, explaining that in other countries (at least in Australia), you get a new credit card number so thieves can't use the old number online. But the officer was convinced card numbers were immutable. The passenger did have a police report, but the German officer said "This case number is for British Police, checking this is too difficult."<p>The inspector asked for the passengers passport - understandably the passenger was not about to surrender his main identification to someone else. The inspector said he could not assist if he did not see the passport, and the passenger then allowed him to <i>see</i> the passport. But when he provided it, the inspector looked at it, then said "Thank you, I now take this, you do not get this back until the police arrive and the police will decide if they give it back to you."<p>The passenger was part of a tour group, and all of the other tickets had been valid. They asked if they would all be arrested, the inspector said no, but when they asked if they could accompany him to the police station, the inspector said "No, you are not allowed to, only he can go with the police." The entire group all got out at the next stop anyway, where the passenger was arrested by police. After an argument the police did allow the tour group to follow, at least through Munich Station for as far as I could see.<p>TLDR: the passenger had a successfully pre-purchased ticket, had passport identification that matched the payment details, bank & police statements to support his story of a stolen credit card, but he was still arrested by Munich police. And Munich was only a stop they were passing through during their train journey! I adore Germany, but seeing this left a terrible impression. That Deutsche Bahn card ID policy is crazy, and something is very wrong with Munich's authorities. I'll stick to Berlin next time.