US President Barack Obama has said there is "no excuse" for police who use excessive force against protesters in Ferguson.
In a speech at the White House, he urged everyone involved to hold themselves to a "high standard", including protesters, and warned troublemakers not to use the shooting of teenager Michael Brown as an "excuse" for their behaviour.
He also used the speech to condemn the arrests of two journalists covering the riots.
There is never an excuse for violence against police, or for those who would use this tragedy as an excuse for vandalism or looting.
There is also no excuse for police to use excessive force against peaceful protests, or to throw protesters in jail for lawfully exercising their First Amendment rights.
And here in the United States police should not be bullying or arresting journalists who are just trying to do their jobs, and report to the American people about what they see on the ground.
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