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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It has been confirmed that the 2015 world tour of top Gear Live will go ahead, renamed Clarkson, Hammond and May Live.
A new ITV news/ComRes poll in Scotland suggests there is serious trouble ahead for Labour.
Two gangs of warring criminals are behind a string of violent gun, knife and grenade attacks in Greater Manchester, police have revealed.