Police said Monday they had arrested 100 people in a second night of rioting in London, condemning it as "copycat" disorder following weekend unrest sparked by the death of a man in a police shooting.
As violence which rocked the multi-ethnic northern district of Tottenham on Saturday spread to other districts of the capital, doubts emerged over the original version the shooting of 29-year-old Mark Duggan, with suggestions that officers were not under attack when they opened fire.
Nine police officers were injured Sunday as youths attacked shops, cars and threw missiles at police in the southern district of Brixton, in Enfield, Walthamstow and Islington in the north, and on Oxford Street in the city centre.
Police had braced themselves for "copycat criminal activity" following rioting in Tottenham on Saturday night, after several hundred people held a peaceful protest against Duggan's death.
Homes were torched, two police cars and a double-decker bus were set ablaze and shops looted in Tottenham in the worst such unrest in London for years, less than 12 months before the city hosts the Olympic Games.
At least nine police officers were injured overnight Sunday, including three who were taken to hospital after being hit by a speeding car, after 26 were hurt on Saturday.
"Officers responding to sporadic disorder in a number of boroughs made more than 100 arrests throughout last night and early this morning," Scotland Yard said on Monday, after 61 people were arrested on Saturday night.
"Officers are shocked at the outrageous level of violence directed against them," a police spokesman said.
Police deployed extra officers in flashpoint areas on Sunday night, but there was still widespread looting, with young men seen walking out of ransacked stores laden with electrical goods.
In Brixton, which like Tottenham has a long history of tensions with the police, hundreds of people raided an electrical superstore, a Foot Locker sports goods store was set alight, and several shops had their front windows smashed.
Surveying the damage on Monday morning, Marilyn Moseley, a 49-year-old sales advisor, condemned the Brixton riots, which had followed a free local street party.
"I heard the helicopters out last night after the street party. It was inevitable something would happen after people were out drinking all day. Anger isn't the word -- it's pointless," she said.
Shops were also looted in Enfield, a north London suburb three miles (five kilometres) from Tottenham, and there were reports of two vehicles being set on fire.
Unrest also erupted in Walthamstow, north London, where more than 30 youths, many in masks, vandalised shops.
About 50 youths also gathered in Oxford Circus, on the world-renowned Oxford Street shopping artery, causing some damage before police intervened.
The Tottenham riots erupted after a march in protest against Duggan's death on Thursday.
He was shot in an apparent exchange of gunfire with police as he travelled in a taxi after officers had stopped the car during an operation against gun crime among the black community.
Newspaper reports Monday suggested that tests conducted on a bullet found lodged in a police officer's radio after Thursday's shooting came from a police weapon. Police are investigating the death.
Police have said the killing of Duggan, a father of four children, was "absolutely regrettable" and the Independent Police Complaints Commission (IPCC) has launched an investigation.
But the shooting caused huge anger in Tottenham, one of the capital's most deprived areas.
Tottenham has a history of tensions with police, and was the scene of the brutal murder of police constable Keith Blakelock, who was hacked to death on the Broadwater Farm estate during rioting in 1985.
Prime Minister David Cameron's spokesman condemned Saturday night's violence as "utterly unacceptable", and on Monday Home Secretary Theresa May warned that those responsible would be punished.
"Those responsible for the violence and looting will be made to face the consequences of their actions," May said.
"Londoners have made clear that there are no excuses for violence and I call on all members of local communities to work constructively with the police to help them bring these criminals to justice."