A dispersal zone set up to tackle anti-social behaviou has been extended.
With the support of Harrow Borough Council, police have renewed the zone covering Harrow town centre following consultation with businesses and councillors.
Officers will be able to order groups of people found causing anti-social behaviour in the area to leave and not return with 24 hours.
Those found to have returned can be arrested and face being jailed up to three months or being fined up to £2,500.
Borough commander Chief Superintendent Simon Ovens said: “Dispersal zones are a highly effective way of dealing with anti-social behaviour, which I know is of considerable concern to Harrow Residents.
“I can assure everybody that we will make robust use of this power in our efforts to make Harrow one of the safest boroughs in London.”