LONDON (AP) -- Female genital mutilation, commonly associated with parts of Africa and the Middle East, is becoming a growing problem in Britain despite efforts to stamp it out. London's Metropolitan Police, Britain's largest police force, hopes a campaign beginning on Wednesday will highlight that the practice is a crime here.

To make their point, police are offering a $40,000 reward for information leading to Britain's first prosecution for female genital mutilation, Detective Chief Superintendent Alastair Jeffrey said.

In Britain, the problem mostly involves first-generation immigrants from Africa and the Middle East.