Ferguson protesters dispersed

Police managed to disperse protesters from the streets of Ferguson, Missouri, early on Wednesday, following a night of largely peaceful demonstrations.

More than 2,000 National Guard troops were deployed overnight across the St Louis area, including the suburb of Ferguson, as authorities sought to prevent the type of wide-scale rioting, looting and arson seen the previous night.

Monday's violence was sparked by a grand jury decision that there was not enough evidence to prosecute Darren Wilson, the white police officer who fatally shot unarmed black teenager Michael Brown on August 9.

"Generally, it was a much better night," St. Louis County Police Chief Jon Belmar told reporters on Wednesday, adding that there was very little arson or gunfire, and that lawlessness was confined to a small group.

Missouri State Highway Patrol officer Ron Johnson described the protests as mostly peaceful, and said some demonstrators had helped police maintain calm.

Despite security reinforcements, however, vandals still managed to torch a police car in front of the town's city hall, and smashed several of the building's windows. St Louis police reported this was the only time they had to use tear gas. Forty-four people were arrested in total.

Large protests over the grand jury decision were also held in other cities across the United States overnight, including New York, Los Angeles, Washington, Seattle, Boston and Atlanta.

Brown's death reignited a nationwide debate about US race relations, the use of firearms, and the sometimes strained ties between African-American communities and police.

Earlier on Tuesday, a lawyer for Michael Brown's family said the grand jury's failure to indict Wilson was "completely unfair" and that the criminal justice system was "broken."

Police officer speaks

In his first public statement since the shooting, 28-year-old Wilson told ABC news he had a clear conscience, as he felt he could not have done anything differently in the confrontation with Brown.

"The reason I have a clean conscience is because I know I did my job right," Wilson said.

"I don't think it's haunting. It's always going to be something that happened." He said the situation would have ended in the same way had Brown been white, as he feared for his life and acted out of self defense when Brown attacked him.

"I gave myself another mental check. Can I shoot this guy? Legally, can I? And the question that I answered to myself was, 'I have to.'"

African-Americans and others in the Ferguson community had called for Wilson to face prosecution for murder or manslaughter. Many were enraged when the 12-member grand jury, responsible for reviewing hours of testimony and tape recordings, found "no probable cause" to indict the officer.

In comments on Tuesday, Obama called for dialogue and deplored the outbreak of violence. He said offenders should be prosecuted, but added that he understood why so many people were upset.

"The frustrations that we've seen are not about a particular incident. They have deep roots in many communities of color who have a sense that our laws are not always being enforced uniformly or fairly," Obama said.

nm/ (Reuters, AP, dpa)