Polish border security detained a French traveller on Friday who was trying to smuggle his Russian wife into the EU in a suitcase.
The authorities stopped the man, said to be in his sixties, at the eastern border town of Terespol, the Telegraph reported.
The officers were initially suspicious at the size of the man's luggage and were shocked to discover the woman, in her thirties, hidden inside.
Border guard spokesman Dariusz Sienicki said: "She was alive and well and didn't require medical attention."
The couple, who were traveling from Moscow to Nice via train, were released after questioning.
It seems they were unaware that, thanks to the Schengen agreement, there would have been no issue with the woman entering the country anyway.
The Moscow Times reports that the couple were allowed to return to Belarus without charge.
Sienicki added: "This was the first time I've seen someone travel like this. She very well could have been a victim of human trafficking."
Police have said that around 100 people a year attempt to get through the border and those who are caught could face as much as three years in prison, RT reported.
The officers caught up with a man after becoming suspicious of the large suitcase he was carrying, when they opened it they uncovered a 19-year-old sub-Saharan man curled up inside.
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