A state of emergency order has been passed by the governor of Missouri and a curfew has been imposed from midnight to 5am.
This comes in response to looting after racial tensions boiled over once more in the wake of the police shooting of an unarmed black teen.
Protesters clashed with riot police overnight.
Police reports had said a black teen was a suspect in the theft of cigars from a shop minutes before an officer shot him dead.
Ferguson in Missouri had been calm over the previous 24 hours after local law enforcement was replaced by state police led by an African-American captain.
However, racially charged protests yesterday entered their sixth night since the death of Michael Brown on 9 August.
Highway Patrol Captain Ron Johnson said police fired a teargas cannister at a crowd near a shop and broader violence and looting erupted.
Police reports released yesterday did not explain what, if anything, Mr Brown's suspected theft had to do with the fatal encounter.
There remains little clarity surrounding the moments leading up to Mr Brown's death.
The unarmed teenager died after being shot by a white police officer.
The allegation of theft reignited anger in the St Louis suburb of Ferguson.
The 18-year-old student's family have accused police of character assassination even as the investigation into his death continues.
Incident reports from the Ferguson police department linked Mr Brown by name to the theft of a $49 (€37) box of cigars from a shop.
The robbery happened about 20 minutes before he was shot in broad daylight on a nearby street.
Police released surveillance footage showing a tall black man - in a t-shirt, khaki shorts and sandals, the same outfit Mr Brown was wearing - grabbing a shop clerk by the shirt and shoving him.
Ferguson police chief Thomas Jackson also identified the officer who shot Mr Brown as Darren Wilson, who is 28.
The six-year veteran of the force had responded to a 911 call about the robbery.
In a statement to reporters, Chief Jackson stopped short of linking Mr Brown by name to the theft of cigars from a shop.
But the connection was made in an incident report, that summarised the content of surveillance video from inside the unidentified corner shop that was allegedly robbed.
The FBI and federal Department of Justice are pursuing a civil rights investigation.