Police have arrested more than 100 people in a second night of violence in London triggered by anger over the fatal shooting of a man by police last week.
Groups smashed and looted shops and damaged a police car in Enfield, a few miles north of Tottenham, which saw the British capital's worst unrest in years on Saturday night when a police station came under attack amid protests over the death of Mark Duggan, a father of four who was gunned down by police on Thursday.
The multi-ethnic neighbourhood of Tottenham, where the rioting began, has a history of racial tension, with locals - especially Afro-Caribbean residents - resenting police behaviour, including the use of stop and search powers.
Police said on Monday they had responded to what they called "copycat criminal activity" across London.
There was looting in a number of boroughs in north, east and south London by small and mobile groups. And groups of youths continued to attack police officers, damaging a number of police vehicles.
"It's not so easy to explain the violence of the past two days," Al Jazeera's Barnaby Phillips said, reporting from the riot-hit areas of London. "It began in the north London neighbourhood of Tottenham and the catalyst was the killing by police of a black man.
"But British politicians say racial tensions - or poverty - don't justify what has happened since that death ... There are skirmishes, running battles with youths throwing stones."
Christine Jones, a police commander, said the police had "extra resources" on duty across the capital on Sunday night.
"We know we have been victimised by this government, we know we are being neglected by the government. How can you make one million [people] unemployed and expect us to sit down?"
There had been "sporadic disorder" in a number of boroughs throughout the night, with more than 100 people detained, on top of 61 arrested on Saturday night and Sunday morning, she said.
"Anyone else who thinks they can use the events from last night as an excuse to commit crime will be met by a robust response from us," Jones said in a statement.
Three shops were damaged, and two of them looted. In Enfield, the rear window of a police car was smashed, police said, adding that several people had been arrested.
'Glimpse into the abyss'
Police said officers were shocked at the level of violence directed against them.
At least nine officers were injured overnight in addition to the 26 injured on Saturday night, as rioters bombarded them with missiles and bottles, looted buildings including banks, shops and council offices, and torched three patrol cars near the Tottenham police station.
Prime Minister David Cameron's office described the rioting as "utterly unacceptable".
The Metropolitan Police said on Twitter on Sunday night: "Police are responding to a significant amount of criminal activity across London and are deploying officers to tackle it."
There was concern that the riots were fuelled by posts on social media sites and that the process might continue in the days to come.
Police Commander Adrian Hanstock told the Reuters news agency there was "a lot of ill-informed and inaccurate speculation on social media sites" that could inflame the situation.
"Should we receive any indication that there will be any further violence or offending, there is a robust policing plan in place and we will respond appropriately with the resources available to us," he said.
The devastated Tottenham area still smoldered on Sunday as two police helicopters hovered over the burnt-out buildings, a witness told reporters, adding that the district resembled a war zone.
Echoes of past violence
The riots that resulted came amid a British economy struggling through deep public spending cuts, tax hikes and rising unemployment.
Tottenham has a large number of ethnic minorities and includes areas with the highest unemployment rates in London.
The march against Duggan's death began at Broadwater Farm, a 1960s-era housing project in Tottenham that is notorious across Britain.
"We know we have been victimised by this government, we know we are being neglected by the government," said a middle-aged man who declined to give his name. "How can you make one million [people] unemployed and expect us to sit down?"
In 1985, the estate was the scene of some the worst urban rioting in Britain during the past 30 years following the death of Cynthia Jarrett, a local woman who died during a police search of her home. A police officer was subsequently stabbed to death in the violence.
Relations have improved but mistrust remains, and the shooting of Duggan - a popular figure in the community - has stirred old animosities.
Very few details of Duggan's death have been released. Police said initially an officer was briefly hospitalised after the shooting and media reports said a bullet had been found lodged in the officer's radio.
The Independent Police Complaints Commission, which is investigating the shooting, released a statement saying a "non-police firearm" was recovered at the scene.
Although a gun was recovered from the scene, The Guardian newspaper reported that the bullet in the radio was police-issue, throwing doubt on speculation that Duggan had fired at an officer.