The police watchdog has opened a homicide investigation into the death of Chris Kaba.
Crowds have gathered outside New Scotland Yard, the headquarters of the Metropolitan Police Service, in protest against racism and police brutality.
The rally follows the fatal shooting of a 24-year-old unarmed black man, Chris Kaba, by an officer from the Met on 5 September.
The police watchdog, the IOPC, is investigating what happened, and will also look at whether race was a factor.
Politicians, including Jeremy Corbyn, joined the protest in central London.
Mr Kaba died after a single shot by a firearms officer at the Met, who has since been suspended from duty.
He had been involved in a police pursuit after the car he was driving was flagged on an automatic camera system indicating it had been involved in an offence.
Mr Kaba’s family have accused the Met of racism.
The mayor of London, Sadiq Khan, said the IOPC “must go wherever the evidence takes them”.
He added: “I fully understand the grave concerns and impact of Chris Kaba’s death on black Londoners across our city and the anger, pain and fear it has caused across our communities – as well as the desire for justice and change.
“The IOPC have confirmed to me that they are fully committed to carrying out a thorough and comprehensive investigation to establish all of the facts – with all key findings made public.
“I’m clear that the independent investigation must be fearless and leave no stone unturned.”
The IOPC said it had been in contact with Mr Kaba’s family regarding the investigation, which is expected to take six to nine months to complete.
A coroner’s inquest into the death is due to open on 4 October.
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