In La Coruña, northern Spain, a tiny scrap of paper has got everyone talking. On it are the winning numbers of last year's lottery, worth €4.7m (£3.95m). Nothing is known about its owner except that he or she has no idea they are now extremely rich .

According to the Galician newspaper La Voz, someone bought the ticket carrying the winning numbers 10, 17, 24, 37, 40 and 43 last year in a Carrefour shopping centre in Galicia but failed to keep it safe.

So when the numbers were drawn in June 2012, the prize went unclaimed.

The mislaid ticket was found on the counter of a different lottery shop, suggesting the winner likes to play the numbers in multiple locations. Rather than try to claim it, the good samaritan who found it, Manuel Reija González, informed lottery administrators, and so began the long process of confirming its veracity.

Now the hunt has begun to find the lucky ticket buyer. Whatever happens, there will be a happy ending of sorts, because if the owner doesnt show up within two years, the prize will go to Reija González, rewarding his honesty. There is just one strange detail – Reija González's brother works for the lottery, as did his father and grandfather.

The mayor of La Coruña, Carlos Negreira, said on Monday: "For the first time we're looking for a millionaire, not because we want money from them, but because we want to give it to them."

The town hall has provided some information about who they are seeking, but it won't be easy to fool them. They have kept back some important details to make sure the right person claims their winnings, including the exact time the ticket was bought. Perhaps the numbers are the ones the winner always uses, or match their birthday, or some other significant date. According to the law, "the prize can only be paid out if sufficient information is provided that proves without doubt that the claimant is the rightful" winner. One man has already tried to claim the prize, but has been rejected.

In a country hit hard by recession, with unemployment above 27%, the news has made the headlines on the main national TV shows.

It is not the first time a winning lottery ticket has caused such commotion. In 2001 a British couple lost out on a £3m payout after mislaying their ticket, despite convincing Camelot that they were the rightful winners.