The Metropolitan Police chief said a campaign launched to identify possible victims of female genital mutilation (FGM) "warns" people of the law.
Sir Bernard Hogan-Howe said: "They have an option to stop - the fact they bought a ticket to me is irrelevant.
"They should not be committing a serious attack on a child and they should not be breaking the law."
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Unsurprisingly the birth of the Duke and Duchess of Cambridge's daughter has dominated Sunday's front pages and taken up many column inches.