Parts of a story written by an investigator from The Sun who claimed to have travelled from Turkey to Paris without having to show his passport were made up, the Croatian Interior Ministry has said.
In an article billed as "a damning exposure of Europe's lax borders", Emile Ghessen says he smuggled himself 2,000 miles in six days without showing his passport once.
The story says the path he took was similar to the route used by some of those responsible for the terror attacks in Paris, and by many refugees.
However, the Croatian Interior Ministry said it had proof parts of the story were made up - and published a scan of his passport that it said it made during border checks.
The article said Mr Ghessen evaded border police by hiding in a toilet when his train was stopped at the Croatian border, leaving the door unlocked so it appeared unoccupied.
"The police never checked the toilet," he wrote. "Four hours later I was in Zagreb and spent the night in a hostel."
But the Croatian Interior Ministry's statement said this part of the story was untrue.
The statement reads: "Police Directorate denies part of the article published on the website of the British newspaper The Sun, which claims that a journalist managed to pass through Croatia without being checked by the Croatian border police.
"In fact, Croatian border police registered Emile Pierre Ghessen on 23 November at 2.10 pm at the Tovarnik railway border crossing where he entered the Republic of Croatia, and on 24 November at 5.20 pm at the Zagreb Airport border crossing, where he exited the Republic of Croatia."
The story, which appeared on page 26 of The Sun on Saturday, has since been removed from their website.
On Facebook, Croatian Interior Minister Ranko Ostojić wrote: "I am glad when the police quickly finds liars like these, so-called professional journalists, and catch them lying about hiding in a toilet where they belong, together with the newspapers which employ them."
Facebook and Twitter accounts thought to belong to Mr Ghessen have since been closed.
A spokesman for The Sun said: "The Sun is currently investigating concerns that have been raised about this story.
"The journalist concerned is not a member of The Sun's staff but a freelance documentary maker, whose work has been used by national broadcasters, newspapers and websites."
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