More than 2,000 teachers, many of them British, replied to an advert offering them work in a Botswana school.

The school does not exist, and applications had to be sent to a box number. All applicants received a letter saying they had been successful and asking for up to $100 (Pounds 62) to cover the cost of visas and work permits.

A man was arrested in Gaborone, Botswana’s capital, after an international police operation caught him collecting applications and $4,000 from the post office box.

Adverts for jobs at Southwood Education Centre in Botswana were placed at a university in Ghana, but police believe they also appeared in Britain because of the number of British applications found on the arrested man.

Ashwin Kumar, of Interpol’s National Criminal Intelligence Service in London, said: “This was a cruel hoax that took advantage of professionals wanting to take up what could have been a genuine career opportunity. Each person may have only lost a small amount, but the adverts received so many applications that this conman must have made big money - probably more than $200,000.”

“Anyone asked to send money in this way should always question why. Even if there is no way of verifying the identity of the person asking for money, they can check what normal procedure in that country are by contacting its embassy for example.

“In this case, applicants should have been suspicious because you would normally apply for your own visa at the relevant embassy in this country and expect an employer to arrange a work permit without asking for money up-front. ”