Residents and business owners in the town of Ferguson are seeking a return to normal ahead of the Thanksgiving holiday on Thursday, clearing debris after days of violent protests. This comes after a legal decision not to prosecute the white policeman who shot dead unarmed, black teenager Michael Brown last August.

That anger continues to simmer in other cities across the US, however, with demonstrations occuring in Boston, New York, Los Angeles, Dallas and elsewhere. Police have arrested a total of around 400 people in Ferguson and across the US since Monday's ruling.

Brown's death reignited a nationwide debate and highlighted long-standing tensions over race relations, police tactics and the use of firearms. A demonstration in London (seen above) on Wednesday saw thousands march, chanting the slogan "hands up, don't shoot."

More than 2,000 National Guard troops are deployed across Ferguson, on orders from Missouri Governor Jay Nixon. On Tuesday evening, protesters set a police car on fire and broke windows at the City Hall.

It's hoped the heavy presence of guardsmen will prevent a repeat of the more violent scenes on Monday, when riots, looting and arson broke out following the announcement of the grand jury's decision.

National Guard troops with rifles were posted at intersections in Ferguson on Wednesday and in several parking lots where stores had been looted or burned.

There were no serious confrontations after nightfall on Wednesday, but a few dozen protesters were seen shouting at troops outside the police department.

Also on Wednesday, authorities said the body of a 20-year-old man, identified as Deandre Joshua, had been found inside a car in Ferguson. They said the man had been shot. His death is being investigated as a homicide but police have not set whether it is connected to the wider violence in the town.

The man who shot Brown, officer Darren Wilson, has told US media his conscience is clear. He said he feared for his life, accusing Brown of starting their confrontation.

Brown's family say they are devastated by the ruling not to indict Wilson, and believed his version of events to be false. Brown's mother, Lesley McSpadden, labeled Wilson's words "insult after injury" and "disrespectful."

jr/jm (AP, Reuters, AFP)