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Is carrying a passport mandatory, to travel from Germany to Czech Republic and back for a non-European citizen? The persons have with them a valid Blaue Karte with them issued by Germany which they intend to carry.
If it is important, the persons in question are Indian citizens whose passports are currently not with them though they will be getting them back after a few days. The intended mode of travel is Deutsche Bahn and Flixbus.
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Even if there are no fixed immigration checks at the German land borders anymore, both German and foreign citizens are required by law to carry a valid travel document (passport or EEA national id card) when crossing the border.
Is carrying a passport mandatory, to travel from Germany to Czech Republic and back for a non-European citizen?
Jain (yes an no!)... if you get controlled you can show your blue card, but since that ID is related (strictly linked) to your passport ID then you could be required to show your passport too (even inside EU Zone)...
personal anecdote: traveling by bus from Germany to Austria, Austrian police will ask you for the passport and will not accept a completely identification mode as only showing a residence permit...
I would in your case bring both...
