Police ramped up their presence on the streets of London Tuesday, but the violent disruptions and looting that plagued the capital in previous nights continued in other British urban centres.
The metropolitan police noted earlier in the day that resources have been "stretched" in London in recent days, but they said more than 16,000 officers would be deployed as they tried to quell the riots.
After three nights of riots and unrest, little trouble was reported Tuesday in London.
"With so many policemen on London's streets the rioters seem to be lying low, but so are the people," CBC's Nahlah Ayed said from London.
Metropolitan police said 685 people had been arrested in London in recent days — of those, 111 have been charged.
Britain's Crown Prosecution Service said it had teams of lawyers working 24 hours a day to help police decide whether to charge suspects, allowing them to quickly clear police station cells.
Police forces in other cities were also reporting arrests as the vandalism and violence swept through Manchester, Nottingham, Birmingham and several other cities.
In Manchester, police said they were dealing with "extraordinary levels of violence from groups of criminals intent on committing widespread disorder" as windows were smashed and stores were looted.
Witnesses at Manchester's main shopping area of Market Street reported plumes of thick smoke filling the air after looters set fire to a Miss Selfridge store. Transport officials also suspended service on the Metrolink tram that runs through the city centre, and police advised people to stay out of the area.
Nottinghamshire police said that a police station in the Canning Circus area of the city's centre came under a firebomb attack by a group of 30 to 40 men. The fire was extinguished and there were no reports of injuries, but police said at least eight men were arrested at the scene.
Later Tuesday, police said fires have been seen in many locations and "a number of cars were firebombed" in Nottingham.
In central England, police said they made five arrests in Birmingham and dispersed a small group of people who torched two cars in the centre of West Bromwich, a nearby town. Shops were targeted by rioters in the city of Wolverhampton, police said.
There also were minor clashes for the first time in the central England locations of Leicester, Wolverhampton and West Bromwich.
'Full force of the law'
The fresh outbreak of violence came after British Prime Minister David Cameron vowed to do everything necessary to restore order and punish those responsible for the violence.
Cameron cut short his holidays to return to London to address the worst rioting in the country in decades, warning that the culprits "will feel the full force of the law."
According to the BBC, police have also started releasing images and footage of people wanted for questioning in connection with the unrest.
The rioting began late Saturday in London's northern Tottenham district when a peaceful protest over the police shooting of a local man turned violent, leaving parts of the street charred and its shops looted.
Some have blamed the unrest on unemployment, insensitive policing and frustration across Britain over the government's austerity budget, which will bring deep cuts to social services and welfare payments.
Greater Manchester police assistant chief constable Garry Shewan appeared to dismiss that notion Tuesday, saying the unrest in Manchester and Salford was "nothing more than senseless violence with no absolutely no regard for people, their property or livelihoods."
Earlier Tuesday, residents of London's affected areas banded together to clean up the aftermath of looting in their communities, but some expressed concern that the disorder would continue.
Many residents of the communities hit by violence have complained that police responded too slowly or in too few numbers to quell the troubles in previous nights.
John Comyn was part of a group of people who tried to keep looters out of the shops in the Clapham area Monday night.
He said a core of about 20 people stood together to try to repel the looters, but as many as 50 people pitched in to try to protect the local businesses.
"Anybody who was wearing a mask or a hood — we just told them there was nothing for them beyond us, stick to where you've ruined already, and they just weren't to get past us."
Comyn said he knew the police were stretched, but he noted that he didn't see a single officer while he was out Monday.
At least one death is being blamed on the riots, with officials confirming a 26-year-old man shot in a car in the London suburb of Croydon during Monday night's violence has died in hospital.
In London's Hackney district, hundreds of youths left a trail of burning trash and shattered glass. Looters ransacked a small convenience store, filling plastic shopping bags with alcohol, cigarettes, candy and toilet paper.
"This is the uprising of the working class. We're redistributing the wealth," said Bryn Phillips, 28, a self-described anarchist, as young people emerged from the store with chocolate bars and ice cream cones.
Tensions over police shooting
Also on Tuesday, the Independent Police Complaints Commission, a watchdog agency investigating last Thursday's shooting of Mark Duggan, 29, announced there was no evidence he fired at police. An illegal firearm recovered at the scene had not been fired, the watchdog said.
The shooting of Duggan, a black man, in a neighbourhood with a history of tensions between police and young people triggered immediate outrage in the community over police abuses and demands for independent inquiries into the officers' actions.
Police said Duggan was shot dead last week when police from Operation Trident, the unit that investigates gun crime in the black community, stopped a cab he was riding in.
The IPCC said police involved in the shooting insisted there was a threat of life in the confrontation that led to Duggan being fatally shot.