More than 1,000 arrests have been made and about 600 people charged over three days of rioting and looting in London.
Police said among those held was a man aged 19, in Haringey, east London, who posted a picture of himself on Twitter, posing with suspected stolen goods.
An increased police presence of 16,000 will remain on the streets throughout the weekend, the prime minister said.
The death toll from London's riots rose to two with the death of a 68-year-old man who was attacked in Ealing.
Richard Mannington Bowes, of Haven Green, Ealing, suffered head injuries and went into a coma when he was attacked on Monday night after remonstrating with some teenagers who were setting fire to two industrial bins on Spring Bridge Road.
Previously Trevor Ellis, 26, of Brixton Hill, was found shot in a car in Croydon. Police believe he was shot during a car chase on Monday night following an altercation with a group of people.
On Thursday, the Metropolitan Police said they had been granted about 100 warrants to search homes across London, and they will be executed over the coming days.
'Not enough police'
On Friday morning, a number of addresses were raided, while magistrates' courts sat through the night again to process those charged.
The Met said the 19-year-old man who posted a picture of himself with "a haul of suspected stolen goods" on the micro-blogging site Twitter was detained on suspicion of violent disorder and theft.
Among those charged was a 16-year-old girl accused of two counts of robbery, attempted robbery, possession of a knife, threatening violence and assault on police in Lewisham.
A 15-year-old girl was also charged with attempted robbery and threatening violence over the same incident. The girls were identified by officers, the Met said.
Five males, including two 17-year-olds and one 18-year-old, who were arrested on suspicion of an arson attack on the Sony distribution centre in Solar Way, Enfield, on Monday night, have been bailed until September.
The Met's Deputy Assistant Commissioner Steve Kavanagh has admitted there were not enough police to deal with the three days of rioting.
But Sir Hugh Orde, the president of the Association of Chief Police Officers, said the police's decision to change their tactics helped control the disorder.
On Friday, London Mayor Boris Johnson said the police were doing a "fantastic job" and praised them for the important arrests they have made over the past few days.
He also praised the "heroism" of firefighters who battled the fires across the capital and described the action of rioters who stopped London Fire Brigade crews from reaching the burning buildings as "demented".
'The best commanders'
Acting Met Police Commissioner Tim Godwin praised his officers saying he had some of the "best commanders in the world" who showed "great courage as well as restraint" during the disturbances.
Trouble first flared on Saturday in Tottenham, north London, after a peaceful protest over the fatal shooting of 29-year-old Mark Duggan in a police operation on 4 August.
By Monday night the situation had worsened with disorder spreading to Hackney, Croydon, Clapham, Camden, Lewisham, Peckham, Newham, East Ham, Enfield, Woolwich, Ealing and Colliers Wood.
Officials from the Independent Police Complaints Commission were in Tottenham on Thursday to gather more information about Mr Duggan's shooting, a week on from his death.
His family will hold a wake for him later.