There has been a violent response to a decision by a grand jury in the US state of Missouri not to bring charges against a white policeman who shot dead a black teenager.
Several cars and buildings were set ablaze and shots fired in the St Louis suburb of Ferguson, where Michael Brown, 18, was killed by Darren Wilson in Ferguson on 9 August this year.
State prosecutor Bob McCulloch announced the decision as protesters gathered in Ferguson, the BBC reports.
Protests started after the verdict was announced; Mr Brown's mother burst into tears outside the police department and some in the crowd began throwing objects at a police line.
There have been reports of automatic gunfire, and demonstrators have torched cars and attacked buildings.
Bottles have also thrown as anger ripples through a crowd outside the Ferguson Police Department. Police responded with tear gas and smoke canisters.
The woman organising the protests, social advocacy group M-SLICE director Romona Williams, said the ruling made no sense and was utterly racist.
Ms Williams said she had lost all confidence in the government, police and justice system.
But prosecutor Bob McCulloch said the grand jury carefully considered the evidence, and some witnesses changed their stories. As well, witnesses were not consistent in reporting Mr Brown's hands were raised when he was shot, CNN reports.
"They determined that no probable cause exists to file any charge against Officer Wilson, and returned a No True Bill on each of the five indictments," he said.
"The physical and scientific evidence examined by the grand jury, combined with the witness statements, supported and substantiated by that physical evidence, tells the accurate and tragic story of what happened."
The death had opened old wounds but had also provided an opportunity to address those wounds, Mr McCulloch said.
"For how many years have we been talking about the issues that lead to incidents like this and yet, after a period of time, it just sort of fades away.
"So I urge everybody who is engaged in the conversation, who is engaged in the demonstrations, to keep that going, to stay with that, not to let that go."
Mr Brown's death has sparked weeks of demonstrations, sometimes violent. Police were criticised for responding with military grade riot equipment.
Missouri governor Jay Nixon appealed earlier for calm ahead of the announcement, and a 30-day state of emergency was declared last week throughout Missouri.