Peter Casey was interrogated by US Immigration officials at Dublin Airport

Peter Casey, who ran for President of Ireland in 2018, was interrogated by US Immigration officials at Dublin Airport last Thursday prior to boarding a US-bound Delta flight.

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The day after the incident, Casey said on Twitter that he was “treated disgracefully:”

Treated disgracefully by the US immigration officials at Dublin airport yesterday, rudest people in Ireland! Thankfully they all had American accents. Then you meet nice Americans working for Delta. Check out todays Sunday indo!

— Peter Casey (@CaseyPeterJ) February 9, 2019

On Monday, Casey followed up with:

In fairness, I have travelled over 10 million miles and this was only my second bad experience. Generally that are professional and courteous.

— Peter Casey (@CaseyPeterJ) February 11, 2019

Speaking with The Independent, Casey, who lives in Donegal but owns a US-based recruitment firm, says he “saw a side of America” he had not experienced before last week.

Casey claims that after his Global Entry pass didn't work, he was directed into a holding area by US Immigration.

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There, Casey says he was asked questions including: "Why did you say during the presidential election that you were going to give up your green card?;” "Is it your intention to give up your green card?;” and “Why have you not applied for citizenship?"

During the 2018 Irish presidential election, Casey claimed that if he were elected President of Ireland, he would forfeit his American green card. 

Ultimately, Casey came in second place to President Michael D. Higgins.

Officials also allegedly interrogated Casey on his knowledge of green card rules, whether or not he owned his house in the US, and which country his children were born in.

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Casey says: "I was then given a lecture on the fact that my keeping my green card was stopping someone who deserved one from getting one.

"One of the agents even made reference to comments I had made about Trump on the campaign. They had certainly done their homework."

During his 2018 bid for the Irish presidency, Casey said he was “disappointed” when Trump was elected and slammed the US as a “racist society.”