By Loic Hofstedt
Shots have been fired at a protest marking the first anniversary of the killing of a black teenager by police in the US city of Ferguson.
A day of peaceful remembrance for 18-year-old Michael Brown came to a violent end on Sunday (local time) with the gunfire leaving at least one demonstrator injured.
St. Louis County police said an officer opened fire after coming under "heavy gunfire" and pictures on Twitter showed at least two cars with bullet holes.
Local media reported that one person had been taken to hospital.
Protesters had taken to the streets to mark the anniversary of Brown's death in a fateful encounter on August 9, 2014 with officer Darren Wilson.
The shooting – and a subsequent decision not to indict Wilson – led to violent unrest and set off nationwide protests and intense scrutiny of heavy-handed police tactics in a series of cases that ended in the deaths of unarmed black people.
Sunday's day of remembrance had been peaceful until a handful of protesters grew rowdy later in the evening. At least one shop was looted in the hours ahead of the gunfire, which occurred shortly after 11pm.
A crowd of about 300 people had gathered earlier to mark the anniversary, during which they observed four-and-a-half minutes of silence and released two white doves.
The time represented the four-and-a-half hours that Brown's body lay face down in the street before being taken away.
Many in the crowd wore T-shirts emblazoned with Brown's portrait and the words "Choose Change". Others carried signs, including one that read: "STOP killing black children."
Brown's father, also called Michael, said he was grateful so many people had turned out for the march.
"If it wasn't for y'all this would be swept under the carpet. So I just want to give my love out to y'all," he said to the crowd.
In New York, dozens of people gathered at Union Square to hold a vigil for Brown in solidarity with Ferguson and to call for ongoing demonstrations against police killings of minorities.
About 100 people gathered in Brooklyn earlier, staging a symbolic "die-in" to protest Brown's shooting. Police arrested several people.
One year on, black leaders say they have witnessed a dramatic change in American attitudes toward race but see little being done to enact reforms.
The head of the National Association for the Advancement of Colored People, one of the country's oldest civil rights groups, called the pace of legislative change "glacial".