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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Heavy rain and wind for Scotland and northern parts this weekend with an amber weather warning issued and travel disruption expected.
Heavy rain continues to affect Western Scotland and Northern Ireland
A surgeon linked to two deaths and a series of botched surgeries is to return to work despite an ongoing investigation, ITV News understands