Assistant Commissioner Mark Rowley from the Met said: "We've taken a fresh look at policing London and London's obviously a world city.
"The recent census has shown what a big proportion of people in London come from far-flung places...It's important to us to be able to deal equally well with them as local offenders."
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Stamp duty is to be abolished for first-time buyers on properties up to £300,000, Chancellor Philip Hammond has announced in his Budget.
The money will help pay for mental health and counselling services, regeneration in the west London neighbourhood and a new community space.
The small device was hidden in a grate in the ceiling in the only customer toilet at a Starbucks coffee shop.