Card marking to cheat casinos has been around for years and years. Techniques have changed with technology and yesterday The Times revealed news of a group casino cheats all caught using special contact lenses and marked cards to scam the Princes Casino in Monaco out of €64,000.

The Italian players utilised invisible ink and special contact lenses which showed up the ink in order to beat the table at a number of European venues, before eventually being rumbled in Cannes over the summer.

Alarm bells first went off following a game of stud poker, when three Italian players visiting the Princes Casino on the French Riviera won €44,000 (£38,000). Then after a visit to the same table later that week, the casino-goers made off with €20,000 in just a few hours. Staff recognised them and called the police who found invisible marks on the back of the playing cards, with certain symbols such a cross signifying a king, and a line representing an ace – valuable information to assist in the unusually lucky streak of the three players.

According to the state prosecutor of Grasse, Jean-Michel Cailleau, the three players were all wearing contact lenses that had been modified in order to view the invisible markings. Both the Italian men and their two alleged French accomplices could face up to ten years in prison if found guilty.

A police spokesman said that the strategy was a unique one which proved to be very effective – but only for certain amount of time. "We have never seen anything like this in the region. At first we thought that they were using cameras. Finally we realised that their strategy involved using contact lenses," he added.

Police have so far arrested one of the Frenchmen involved in the scam, who they believe was an employee of the casino. It is suspected that he was responsible for smuggling the marked cards into the gaming establishment.

A lawyer for one of the Italian players has claimed that his client has denied the allegations. “He doesn’t understand why he has been arrested,” stated Maître Jean-Louis Paganelli. “He came to the Côte with a friend to have a good time and only brought a pair of sandals, a towel and a pack of playing cards, but that doesn’t make him a cheat”.