Eight police men were injured overnight in the violence, including one with a head wound, and admitted to hospital after trouble broke out in Tottenham following the killing of Mark Duggan, a father of four, in the firing by the cops.
About 300 people had gathered outside a police station on the Tottenham High Road last evening demanding "justice".
The protest was earlier peaceful but turned violent when police cars were set alight using petrol bombs.
The situation was brought under control by early this morning. The London Ambulance Service said separately that a total of 10 people had been treated and nine taken to hospital.
The protest took the form of a riot when hooded youths gathered and set fire to a bus and other vehicles in the area.
Shops in the area were looted with people seen pushing away shopping trolleys full of goods.
Duggan was killed by a specialist police team that deals with gun crime in London's Afro-Caribbean communities. He was in a minicab when he was challenged by the police team and then killed in an exchange of fire on Thursday evening.
The protests were initially low-key, but turned violent last night. Commander Stephen Watson, of the Metropolitan Police, told BBC News that a significant number of officers had been deployed with the aim of restoring "calm and normality to the area as soon as possible".
Tottenham MP David Lammy appealed for calm, saying: "The scenes currently taking place in our community are not representative of the vast majority of people in Tottenham. True justice can only follow a thorough investigation of the facts".
He added: "The Tottenham community and Mark Duggan's family and friends need to understand what happened on Thursday evening when Mark lost his life. To understand those facts, we must have calm."
The Independent Police Complains Commission (IPCC) spokesperson said: "I understand the distress that the shooting of Mark Duggan has caused to his family and in the community and that people need answers about what happened to him.
"This case (Mark Duggan) was referred to the IPCC immediately and we declared it an independent investigation and sent our investigators straight to the scene in Tottenham, where they took control and remained until late Friday night, supervising the forensic examinations."
An independent investigation means that all aspects are carried out by IPCC investigators, the spokesperson said.
"We are in close contact with Mark Duggan's family and supported 14 family members and friends in viewing and formally identifying Mr Duggan's body. We have been in telephone contact with close family tonight and (will) have further meetings with them tomorrow.
"I have tonight spoken to community representatives and hope to meet with them and others as early as possible. I remain in frequent contact with David Lammy, the local MP. We are still gathering evidence and will release further details about our progress with the investigation as soon as we can," the spokesperson said.
