Parliament is being recalled on Thursday in response to rioting in England, the prime minister has said.
The government's emergency committee Cobra met on Tuesday after rioting spread across London, with violence flaring in other major cities.
"We will do everything necessary to restore order to Britain's streets and make them safe for the law-abiding," David Cameron said in Downing Street.
More than 16,000 officers will be on London streets on Wednesday, he said.
Meanwhile, Scotland Yard said a 26-year-old man shot in a car during riots in Croydon has died in hospital.
Mr Cameron said at least 450 people have been arrested so far.
He condemned what he called "sickening scenes of people looting, vandalising, thieving, robbing".
All Metropolitan Police leave has been cancelled and reinforcements called in from other forces, he said, with treble the number of police than before patrolling the streets of London on Tuesday night.
He told rioters: "You will feel the full force of the law. And if you are old enough to commit these crimes, you are old enough to face the punishment."
The recall of Parliament will allow MPs to "stand together in condemnation of these crimes and to stand together in determination to rebuild these communities", he said.
http://www.bbc.co.uk/news/uk-england-london-14460554