This video from London, England says about itself:
3 February 2015
Footage taken by Cassie Quarless.
From daily The Guardian in Britain:
Americans from Ferguson Solidarity Tour join British activists to protest outside G4S offices in central London
Tuesday 3 February 2015 17.14 GMT
Americans involved in the US Ferguson demonstrations joined British activists on Tuesday to block a major street in central London in protest at security company G4S’s role in the death of Jimmy Mubenga.
G4S security guards Terrence Hughes, Stuart Tribelnig and Colin Kaler were acquitted of the manslaughter of the 46-year-old Angolan deportee in December. A coroner had previously found that Mubenga died of cardiorespiratory collapse as a result of restraint on a British Airways deportation flight in October 2010.
More than a dozen activists occupied the balcony of Sutton Park House, Victoria Street, where G4S has offices for a moment before walking out and unfurling a banner that read “Ferguson, Palestine, UK, Stop Racist Killings, Stop G4S” onto Victoria Street. …
The tactic of blocking traffic – known as “shutting shit down” – has been quite prominent in the protests to show solidarity with Michael Brown, Eric Garner and other black people killed by police in the US.
“We’ve been shutting shit down since August 9th  both in Ferguson … and throughout the entire country, including where I live in Los Angeles, where we’ve been able to occupy the headquarters of the LAPD for seven days, and this is a common practice, of shutting shit down,” she said.
“It’s our form of boycott. What we have been able to do is a few things: disrupt people’s lives because our lives are often disrupted by people’s racism and other people’s racism, so we disrupt people’s lives for 20-30 minutes or a couple of hours.” …
Cullors said the tactic had helped draw the attention of elected officials and led to invitations to meet them. “We’ve also been able to drop economies, like on Black Friday we shut shit down and it brought down the revenue by 11%.”
She explained why the Ferguson Solidarity Tour had come to Britain: “The similarities between the UK and the USA is that both of our countries are invested in racism. Some of the differences are the technical differences around the apparatus of law enforcement accountability, but the same thing is dealt to victims of police and state violence – which is no accountability.”
She added: “We have to spread our ideology too of shutting shit down and ideology of making sure we take risks so we can achieve gains for our present and our future.”
NUS black students officer Malia Bouattia, a key organiser of this action and the Ferguson Solidarity Tour, said: “For far too long we have seen successive governments violently deport innocent black men … ”
She also attacked the justice system in relation to deaths in custody. “Not a single police officer has been held accountable for the deaths under police custody and we will not rest till we achieve justice,” she said.