The Seaham family were sent a letter claiming they had won £500,000.
Although sceptical, they called the number and became convinced it was genuine, transferring almost £300 in cash for an administration fee.

But from there the gang, believed to be based in Spain but of west African origin, tricked them out of more than £10,000 in amounts they said were for taxes, insurance and other fees.

The couple, who are in their 30s and have asked police not to reveal their identity, are said to be devastated after realising what had happened.

It is the second time in six months an East Durham family has lost money to a fake lottery.

In November, Edward Smedley, 69, and his wife Margaret, 59, from Peterlee, lost £9,500 to a similar con. Police estimate the it will take the Smedleys seven years to pay off the bank loan they took out to pay the gang.

Investigations are ongoing into both incidents.

Durham Constabulary has said the area is being deluged with scam letters and has logged more than 50 complaints in recent days from concerned residents who have received foreign lottery letters.

Detective Inspector Geoff Smith, head of Durham Constabulary's economic crime unit and former Seaham community inspector, said: "Like a lot of people the latest couple were originally suspicious and left the letter for two or three days.

"But being inquisitive, they rang up and were asked to pay an admin fee.

"They were asked for more and more money.

"They are working people and people like to believe they have won something and think that if they have to give up 5 or 10 per cent of their winnings to get that, it's worth it.

"They are devastated."

Insp Smith said people can be fearful of reporting incidents to police because the con artists have warned the victims they could get into trouble because of illegalities they have become involved in.

He also warned details, such as bank account and passport numbers, handed over to the criminals through the lottery scam could be sold on and used to commit fraud, with similar cons working in countries including Canada.