The shooting death of 29-year-old Mark Duggan, a black man, has sparked riots that started Saturday in Tottenham -- an ethnically diverse, working-class suburb north of London's center -- and have spread to other parts of Britain.
Officers from Operation Trident -- the Metropolitan Police unit that deals with gun crime in London's black communities -- stopped the cab in the predominantly Afro-Caribbean neighborhood during an attempted arrest and soon afterward shots were fired, the Independent Police Complaints Commission (IPCC) said. Duggan, a father of four, was killed. Shooting deaths are rare in England.
With the incident still under investigation, the commission divulged neither who shot Duggan nor why police had stopped the cab.
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The IPCC said Tuesday an illegal firearm had been found at the scene, with a "bulleted cartridge" in the magazine, but there was "no evidence" it was fired during the incident.
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A bullet that lodged in a radio carried by an officer was police issue, the IPCC said.
"A post-mortem examination concluded that Mr. Duggan was killed by a single gunshot wound to the chest. He also received a second gunshot wound to his right bicep," the IPCC said, without saying who fired the bullets.
The man's family and friends, who blamed police for the death, had gathered peacefully Saturday outside the Tottenham police station to protest.
The protest soon devolved into violence as demonstrators -- whose numbers included whites and blacks -- tossed petrol bombs, looted stores and burned police cars.
Metropolitan Police and Duggan's family have appealed for calm. Police said they were stretched thin as they tried to respond to emergency calls -- which were up nearly 400% Tuesday.
British Prime Minister David Cameron's vow of action to quell rioting in Britain's cities was backed up by an increased police presence -- about 16,000 officers were to be on London's streets Tuesday night.
That's more than twice the number on Monday night. Cameron said they are to tackle the "criminality, pure and simple" that has shaken the capital. Officers have been drafted from other cities to help.
"People should be in no doubt that we will do everything necessary to restore order to Britain's streets and make them safe for the law-abiding," Cameron said.
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The trouble -- described by police as "'copycat criminal activity" -- takes place against a backdrop of austerity measures and budget cuts that have led to high rates of unemployment, particularly among the nation's youth.
The violence, which has run into the millions of dollars in property damage, has claimed a fatality -- a 26-year-old man who was found Monday night with a gunshot wound to the head in Croydon, south London, police said Tuesday.
Also Tuesday, police confirmed outbreaks of violence in Wolverhampton and West Bromwich, about 100 miles north of London, and the northwestern city of Manchester. In Manchester, a library and supermarket were ablaze, said Jeff Gill from the Greater Manchester Fire and Rescue.
Cameron, who cut short his vacation in Italy to hold an emergency meeting Tuesday, has recalled lawmakers from their summer break. Parliament is to meet Thursday. He is to hold a meeting of his crisis-response committee at 9 a.m. (4 a.m. ET) Wednesday.
Speaking after the meeting at Downing Street, Cameron said court processes would be sped up to ensure swift justice for those involved in "sickening scenes of people looting, vandalizing, thieving, robbing," many of them apparently teenagers.
"People should expect to see more, many more, arrests in the days to come," he added. "If you are old enough to commit these crimes, you are old enough to face the punishments."
Some 563 people have been arrested in London since the violence began, police said Tuesday. With Metropolitan Police detention cells full, authorities were transporting those they arrested to facilities belonging to surrounding police forces.
Police said 105 of those arrested have been charged. Most of the charges relate to burglary, with other offenses ranging from assault on a police officer to possession of an offensive weapon and handling stolen goods.
In all, 111 police officers and five police dogs have been reported injured, according to a police statement Tuesday afternoon.
"Many officers are still undergoing hospital treatment, some requiring surgery," it said. "Injuries range from fractured bones, serious head injuries, concussion, cuts and sprains, even injured eyes from smashed and thrown glass."
In Hackney, where Monday's disturbances first broke out, Graciela Watson, a mother of two, watched aghast from her home as hooligans, known as "yobs" in Britain, barricaded a normally quiet residential street with burning trash cans and clashed repeatedly with police for more than an hour.
"It seemed like a war zone," she said. "There were youths grabbing bricks from our front wall and hurling them at police."
A resident of Clapham Junction in southwest London, who did not wish to be identified for fear of reprisals, told CNN he had seen groups make repeated trips overnight to his street to fill their cars with looted goods, including televisions and clothes.
The resident said this went on for several hours until police used armored vehicles to disperse them.
"At first I was just, 'OK, it's a bunch of kids letting off steam.' But once they started heavy, heavy looting, and it started getting out of hand, I started getting a bit concerned," he said. "This is not something that's typical of our neighborhood by any stretch of the imagination."
Peckham resident Rebecca Skipwith, a 37-year-old charity worker, told CNN she had passed crowds of "hooded-up kids" and a police cordon on her way home from work Monday. Soon afterward, trouble erupted.
"It's quite bewildering," she said Tuesday. "It was horrible this morning driving to work and seeing the smashed-in shops and glass everywhere. It feels a bit of a wilderness."
Sony Corp. said its only warehouse in London caught fire between late Monday and early Tuesday, with damage but no casualties. The warehouse is in north London's Enfield neighborhood, which has seen scattered protests.
London Fire Brigade said it had "faced its busiest night in recent history," receiving 15 times more emergency calls than usual and tackling "major fires right across London."
Sociology professor Paul Bagguley told CNN that a disproportionate number of young people appeared to be involved in the unrest and that the looters appeared to be motivated by greed.
But people who have spoken to local ethnic minorities also talked of a sense that tension had been building over months, he said, with some upset by police "stop-and-search" tactics.
A community cleanup effort began Tuesday morning in London, with organizers using Twitter to get volunteers together in their local areas, using the hashtag #riotcleanup.
Organizer Dan Thompson, who runs a network aiding small businesses on the south coast, said many thousands of people were supporting efforts to help shopkeepers.
"I thought the quickest, best thing was just to help them get cleaned up this morning, get trading again," he said. "It's a city people love, and to see it destroyed in the way it has been is shocking stuff."
The rioting has forced the postponement of at least two sporting events. England's international soccer game against Holland, due to be played at Wembley on Wednesday, was canceled. And football club West Ham United called off Tuesday night's match with Aldershot Town.
The developments in London came as reports of violence and vandalism flowed in from other parts of the country.
West Midlands Police arrested some 133 people overnight in Birmingham, about 120 miles north of London, Chief Constable Chris Sims said. Officers were making more arrests Tuesday and had released images of suspects, he added.
In Leeds, about 170 miles north of London, police reported no rioting early Tuesday but said there were "pockets of isolated disorder." A car was set ablaze and a man was taken to the hospital with injuries after an alleged shooting.
In Bristol, in southwest England, police said several shops and vehicles were damaged Monday night.
In south Liverpool, about 180 miles northwest of London, police said officers had responded to "reports of vehicles on fire and criminal damage."
London Mayor Boris Johnson, who cut short his holiday in North America, called the violence "utterly appalling."
Questions have been raised about what the disturbances may mean for security during next year's Olympic Games, which London is preparing to host.
A spokeswoman for the London 2012 organizing committee told CNN: "A lot of detailed work has taken place regarding security plans for the Games, and we will continue to review them together with the Met Police and the Home Office over the coming year."
Tottenham has been the site of riots before. In 1985, Floyd Jarrett, who was of Afro-Caribbean origin, was stopped by police near the Broadwater Farm estate in Tottenham on suspicion of driving with a forged tax disc, a document all British vehicles must carry.
A few hours later, officers raided the nearby home of his mother, who collapsed and died during the raid. Rioting erupted shortly afterward, and a police officer, Constable Keith Blakelock, was killed. Like the current violence, a protest outside Tottenham Police Station sparked the 1985 conflict.Tweet