The winning ticket, purchased in Toulouse, has yet to be submitted for collection.

The victim, identified in police records as Jean-David E, had his backpack and bank card stolen from his car earlier this month. Although he asked his bank to block the card, it was already used at a local shop, where two apparently homeless men unknowingly bought a winning ticket.

“They were so totally happy that they forgot their cigarettes and their belongings and walked out like crazy people,” said Jean-David’s lawyer, Pierre Debuisson.

Jean-David has filed a police complaint but is willing to withdraw it if the thieves come forward to share the winnings.

“It’s an incredible story, but it’s all true,” Mr Debuisson said, launching a national appeal on Thursday, urging the men to contact his office to arrange a deal.

“Without them, no one would have won,” he told France-2.

La Française des Jeux (FDJ), the state lottery operator, confirmed that no one had yet submitted the ticket. However, prosecutors may attempt to seize the winnings, arguing they were obtained illegally.

“Time is working against us,” Mr Debuisson warned, noting the ticket will eventually expire.

“You risk nothing… we will share with you,” he urged the thieves. “And you would be able to change your lives.”