The border on the island of Ireland is famously unsecure - except on the few main roads, between the two countries.
When the prices of goods differ significanly in the two, smuggling became a major issue in the past.
Pork prices ensured the growth of pig smuggling for many years - with piglets waking up in another jurisdiction, after nocturnal travel.
Many large farms straddle the border - making such activity easier, and simple to extend to humans.