Home Secretary Theresa May is meeting senior police officers following a second night of violence in London.
Mrs May returned from her holidays after more than 100 people were arrested and 35 officers injured in two nights of rioting and looting.
A peaceful protest in Tottenham on Saturday over the fatal shooting by police of Mark Duggan, 29, was followed by violence which spread into Sunday.
Police are considering arrests for inciting violence through social media.
Mrs May, who had been in contact with other senior politicians and senior police officers while overseas, was meeting Acting Metropolitan Police (Met)Commissioner Tim Godwin and other officers on Monday afternoon.
A spokesman for Prime Minister David Cameron, who is on holiday in Italy, said: "We are very clear that those responsible for that violence and looting will be made to face the consequences for their actions."
On Sunday night three officers were hurt when a vehicle hit them as they tried to make an arrest in Chingford Mount, north London.
Clashes later broke out in Enfield, north London, where shop windows were smashed and a police car damaged.
Up to 200 youths looted shops and charged police in Coldharbour Lane and the High Street in Brixton, south London.
Fifty youths gathered in Oxford Circus, central London, and threw objects at shops and more than 30 youths vandalised and looted shops in Walthamstow, east London.
A spokesperson for the London Fire Brigade said it received 445 emergency calls during Sunday night.
Three fire engines were damaged and crews were called to nine large fires in Edmonton and three fires in Brixton.
The disorder followed rioting in Tottenham, north London, which began on Saturday night and continued into Sunday morning.
Surveying the wreckage in Tottenham High Road Deputy Prime Minister Nick Clegg said the riots would leave "big scars" on the community.
Visiting the scene after returning from holiday on Monday morning Mr Clegg met business owners, local police chiefs, councillors and religious leaders.
'Rotten for London'
He said: "We need to start talking together to identify everything that happened so we can rebuild, not just physically but socially.
"I think the government has to engage actively at all levels and on an ongoing basis."
Metropolitan Police Commander Adrian Hanstock said: "This is not groups of people acting on behalf of communities or with any consent.
"This is individuals who are actually attacking communities, businesses, properties and houses and actually causing a huge amount of upset and criminality."
Kit Malthouse, Deputy Mayor of London and Chair of the Metropolitan Police Authority, said the police did a good job.
Talking about the impact on the capital's image, one year ahead of the Olympic Games, he said: "It's pretty rotten for London, it does not look good.
"What we need to do over the next few months is to underline to people the fundamental truth about London which is that it is one of the safest, great big cities on earth."
Deputy Assistant Commissioner Steve Kavanagh said: "Social media and other methods have been used to organise these levels of greed and criminality."
He described some messages posted on social media sites as "really inflammatory, inaccurate" and said police would consider arresting people using Twitter in relation to incitement to violence.
"That investigation is already under way and that is exactly the sort of thing we are looking at," he said.
Mr Kavanagh pledged that more officers would be on London's streets on Monday night to prevent or tackle further outbreaks.
A candlelit vigil is to be held at The High Cross in Tottenham, between 19:00 and 20:00 BST on Monday.
There have been calls for the government to do more to address the problems faced by young people in the area.
Professor Gus John from the Institute of Education at the University of London said: "Much more attention needs to be given to young people themselves.
"They're talked about a lot - very rarely are they spoken with, very rarely are opportunities made for them to have conversations with themselves."
The Labour MP for Tottenham, David Lammy, said he represented a community with the highest unemployment in London, which desperately needed jobs and investment.
"The deputy prime minister really does now need to respond to the huge need that exists in this community excepting, of course, that violence can never be an excuse for proper political and democratic engagement."
Sixteen people have so far been charged with offences including burglary, violent disorder and possession of a pointed or bladed weapon following the Tottenham riots.
A police officer was also hurt in Thursday's incident where Mr Duggan was killed.
It was described by police as a planned event under Operation Trident, which investigates gun crime in London's African and Caribbean communities.
The results of ballistics tests should be known within 24 hours, the Independent Police Complaints Commission (IPCC) said.
An inquest into Mr Duggan's death is due to open at High Barnet Coroner's Court on Tuesday.