David Cameron vows to do "everything necessary to restore order to Britain's streets as he recalls Parliament and trebles police presence in London. There will be 16,000 officers on patrol tonight.

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Speaking outside Downing Street after holding an emergency meeting with Cobra, the Government's crisis committee, David Cameron condemned the ugly scenes of violence sweeping across Britain.

He said the "sickening scenes" were cases of criminality, "pure and simple, and it has to be confronted and defeated".

Mr Cameron announced that 16,000 police officers will take to the streets of London tonight, more than double the 6,000 on patrol last night. Mr Cameron said reinforcements have been called in from across the country, and all holiday leave for the Metropolitan Police has been cancelled.

Plastic bullets - never used before during UK disturbances - are being considered as "one of the tactics" available to officers.

There have been 563 arrests so far and 105 people charged following the disorder in London.

Parliament is to be recalled for a day on Thursday, he confirmed, adding that court procedures will be "speeded up" and many more arrests will be made.

If you are old enough to commit these crimes you are old enough to face the consequences. David Cameron

"If you are old enough to commit these crimes you are old enough to face the consequences," Mr Cameron said.

Mr Cameron cut his holiday short to return to London in the early hours of this morning, after riots spread across the capital for the third night, and beyond to Liverpool, Bristol and Birmingham.

The PM spoke of his huge sympathy of the innocent families and business owners who have suffered at the hand of the rioters.

He added: "I also feel for all those who live in fear because of these appalling scenes that we've seen on the streets of our country. People should be in no doubt that we are on the side of the law-abiding people who are appalled by what has happened in their own communities."

Causeless copycats

The riots spread from Saturday's isolated case in Tottenham, which flared up from a demonstration after the death of Mark Duggan, to scores of causeless copycat rampages last night.

Scotland Yard Deputy Assistant Commissioner Stephen Kavanagh said there was a "changing nature" in the make-up of the rioters, with the profile changing "dramatically" last night, ranging from 14 to 17-year-olds to "older groups in cars doing organised looting".

This is not about race, faith and class pure and simple. One of the most powerful drivers is about the haves and have-nots. Professor Mike Hardy, Institute of Community Cohesion

E.Nan, a young man from Hackney, east London, said: "We ain't got no jobs, no money. We heard that other people were getting things for free, so why not us?"

The riots have broken out amid a deepening economic gloom, with the economy struggling to grow as the government imposes deep public spending cuts and tax rises.

"This is not about race, faith and class pure and simple," said Professor Mike Hardy, Executive Director of the Institute of Community Cohesion. "One of the most powerful drivers is about the haves and have-nots. It's about those who are excluded."

David Cameron speech after Cobra meeting; recalls Parliament and sends army of police to London streets (Image: Getty)

Government action

MPs will debate action in a recall of Parliament on Thursday, the Prime Minister said.

Keith Vaz, chairman of the Commons Home Affairs select committee, called an emergency meeting for Thursday to consider the terms of reference for an inquiry into the riots. The meeting will not be open to the public.

"It is a tragedy to see that our capital city and other urban centres are being scarred in this way," he said.

"It is important that we look urgently at the causes and policing of what has happened and establish whether the police require additional resources and powers to tackle riots of this scale."

Last night was the worst the Met Police has seen in current memory for unacceptable levels of widespread looting, fires and disorder. Scotland Yard

Mr Kavanagh apologised "that London has got to wake up to these scenes" as he revealed 525 people had now been arrested since rioting began on Saturday.

He said resources were stretched "to an extent never seen before" by last night's "unprecedented" rioting.

Hooded youths ransacked high streets and shopping centres, setting shops and buildings on fire, devastating communities and causing millions of pounds of damage.

Police received almost 20,800 emergency 999 calls last night, 400 per cent more than the usual 5,400.

"Last night was the worst the Metropolitan Police Service has seen in current memory for unacceptable levels of widespread looting, fires and disorder," a spokesman said.

Announcing plans to draw on support from police forces outside London, Mr Cameron said: "As ever, police officers have shown incredible bravery on our streets in confronting these thugs, but it's quite clear that we need more, much more police on our streets and we need even more robust police action and it's that that I've been discussing in Cobra this morning."