US Attorney General Eric Holder has met with community members in Ferguson, Missouri, and vowed a thorough civil rights inquiry into the fatal police shooting of an unarmed black teenager that set off 12 nights of racially charged protests.

Mr Holder, the first African-American to head the Justice Department, spoke in person with students and then community leaders at a community college during a visit to Ferguson for a briefing on a Justice Department investigation into the 9 August killing of 18-year-old Michael Brown.

He later met for about 20 minutes with Mr Brown's parents at the St Louis US Attorney's Office.

No details of the private session were divulged, but a person familiar with the encounter quoted Mr Holder as promising "a fair and independent inquiry" when family members asked him about the investigative process.

Before meeting with Mr Holder, Mr Brown's mother viewed her son's body at a local morgue for the first time since he was shot, the same person told reporters.
Also yesterday, a grand jury began hearing evidence in the case, though protesters stepped up their demands that the local criminal inquiry be turned over to a special prosecutor.

Before a briefing at local FBI headquarters, Mr Holder said the thrust of his department's inquiry differed from the investigation conducted by local authorities.

The Justice Department is seeking specifically to determine whether federal prosecutors can bring criminal charges against Darren Wilson, the police officer who shot Brown, for violating Mr Brown's civil rights by use of excessive force.

His visit came hours after dozens of protesters were arrested in the latest street disturbances.

Many of the protests have been peaceful, but others, especially smaller ones late at night, have been punctuated by looting, vandalism and clashes between demonstrators and police.