An Irishman traveling by bus from Belfast to Dublin was shocked when he was asked to show his passport by Gardaí (Irish police).
The stunned Irishman and fellow passengers had just crossed the border when they were stopped and asked to show passports or photographic ID.
Tristan Drysden, from Derry in Northern Ireland, said he did not have his passport or any other identification to display and was caught "completely unaware."
The check happened on a Translink vehicle shortly after the bus had entered the Republic of Ireland.
"I couldn't believe it when the two guards boarded the bus and started asking passengers for passports," he told The Belfast Telegraph.
"I didn't have my passport on me because I didn't think for a second it was necessary.
"I am not a frequent user of the bus; I usually drive across the border in my car and I have never once been stopped and asked to show a passport or any form of photographic ID.
"I explained to the guard that I didn't have my passport or any form of photographic ID and he said, 'Why not, you are crossing a border?' which stunned me because I assumed people were free to move from one part of Ireland to the other.
"The guard didn't say why he wanted to see my passport so I assumed it was something to do with Brexit and maybe they were preparing for a hard border."
Drysden added that on hearing his Northern accent, the officer told him it was OK.
Bus passenger calls others to carry ID
After speaking to other passengers, Drysden learned that several of them had been asked for passports previously and urged anyone traveling between the Republic of Ireland and Northern Ireland by bus to carry ID just in case.
Irish police have not commented on the matter however, bus company Translink suggested the checks may have been carried out for immigration purposes.
A spokeswoman said: "Occasionally, immigration checks are carried out on cross-border services. We facilitate these checks, which are not related to Brexit."
The Citizens Information Website advises travelers to carry passports for this reason.
According to the Common Travel Agreement between Ireland and the UK, there are no passport controls in operation for Irish and UK citizens traveling between the two countries and a passport is not needed to enter the other country.
How do you feel about being asked for ID on buses in Ireland?
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