Italian finance police today reportedly arrested two men crossing into Switzerland carrying what looks to be around 135 billion dollars worth of US government bonds, potentially the biggest smuggling attempt in history, according to dpa. The Guardia di Finanza was not able to confirm if the bonds were genuine. The would-be smugglers, who were travelling by train, were caught by customs officials more than a week ago. On June 3, finance police conducting a routine check discovered the securities under a false bottom in one of the men's suitcases. The two men - said to be Japanese nationals both over 50 - had not declared the securities, which according to the Guardia di Finanza consisted of 10 so-called Kennedy bonds of a billion dollars each and 249 US government bonds with a face value of 500 million dollars each. The Japanese embassy in Rome confirmed the arrests. The men face potentially very stiff penalties should the securities be found to be genuine, as it is illegal to carry sums over 10,000 euros (around 14,000 dollars) into a non-EU country without declaring it. The Italian state could benefit from the mistake to the tune of 40 per cent of the smuggled sum.