Police have struggled to contain what has become the worst rioting in decades as crowds of youths smashed windows, emptied shops of their goods and set properties on fire.
More than 450 people have been arrested in the capital since Saturday, including three overnight on suspicion of attempted murder after two police officers were hit by a car in Fulton Road, Brent.
David Cameron flew back to Britain to chair the Government's emergency committee Cobra and meet police chiefs, having been on a family holiday to Tuscany.
He described the violence as "criminality pure and simple" and said the Government would do "everything necessary to restore order to Britain's streets and to make them safe for the law abiding".
He said 16,000 police officers will be on the streets tonight and that all Metropolitan Police leave has been cancelled.
The force will also be helped with reinforcements from forces across the country.
Mr Cameron warned those involved in the trouble they were not only risking their own communities, but their own futures, adding: "If you are old enough to commit these crimes you are old enough to face the punishment."
Wednesday's international football friendly between England and Holland at Wembley has been cancelled due to security fears.
On Monday Home Secretary Theresa May condemned "sheer criminality" as police and emergency services were overwhelmed by a third consecutive night of trouble.
The unrest started in broad daylight in parts of east London before spreading as darkness fell.
Scotland Yard was forced to use armoured police vehicles to push back more than 150 people in Clapham Junction , south London, as the disorder hit shops and businesses.
The force said in 24 hours they received 400% more 999 calls than normal (almost 20,800 compared to 5,400).
London Fire Brigade said it experienced its busiest night in recent history, tackling fires across the capital.
It answered 2,169 999 calls between 6pm last night and just after 7am this morning, around 15 times the number it would get on an average day.
Youths also took to the streets of Birmingham, Bristol and Liverpool throughout the night in what officials described as 'copycat' attacks.
West Midlands Police arrested about 140 people in Birmingham after youths rampaged in the city centre, near the landmark Bullring shopping arcade.
Cars were set alight in Liverpool, and police officers were pelted with makeshift weapons including golf clubs as they tried to contain the gangs.
In Bristol, residents were urged to avoid the city centre by Avon and Somerset Police after 150 rioters hit the streets.
London bore the brunt of the violence however , with more than 1,700 extra officers deployed to all corners of the capital.
The "opportunistic" attacks saw major fires set in Hackney and Peckham. A man in Croydon was also injured in a shooting.
A furniture shop in Croydon which had been in the same family for five generations , in a 100-year-old building, was completely destroyed after being torched.
A massive blaze at a Sony distribution centre near Enfield, north London, also sent plumes of thick smoke across the sky.
Sony has warned customers that CD and DVD deliveries may be affected as this was the Britain's main depot for these goods.
Police cells in London are now full.
A spokesman said: "A significant number of arrests were made overnight, leading to all our cells being full and prisoners being taken to surrounding forces."
The Metropolitan Police is planning to publish CCTV images of those involved in the violence.
Acting Commissioner Tim Godwin said: "Those involved in criminality should be under no illusion that we will pursue you."
In Hackney, rioters, many wearing hoods and masks, were confronted by police lines spanning the streets, occasionally moving forward to push the groups back.
Scotland Yard said between 250 to 300 people had gathered on the Pembury Estate, setting alight cars and throwing petrol bombs.
Looting and outbreaks of violence was also recorded by officers in Newham, Lewisham and Bethnal Green, where more than 100 people looted a Tesco premises and two officers were injured.
South of the river in Peckham, teams of riot officers were seen charging at fleeing troublemakers after a major fire was started at a shop adjoining a Greggs bakery.
Experts have estimated that the clean-up will cost tens of millions of pounds but councils across the city have already sent out teams to start.
A Twitter account called @riotcleanup attracted more than 18,000 followers in a matter of hours today and was helping people to co-ordinate their efforts.
Those using the social networking site to co-ordinate clean-up efforts are calling themselves the "Riot Wombles" and are now using the hashtag riotwombles to arrange meeting times and places.
Consecutive days of violence came after a peaceful protest in Tottenham on Saturday, which followed the fatal shooting of Mark Duggan , 29, on Thursday.
An inquest has heard that the father-of-four died of a single gunshot wound to the chest.
Colin Sparrow, deputy senior investigator for the Independent Police Complaints Commission (IPCC), told the brief hearing that their "complex investigation" could take four to six months.
The inquest has been adjourned until December 12.
The Guardian quoted a source as saying that initial tests suggested a bullet found lodged in a police radio after Mr Duggan's death was police issue.
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