Residents of Ferguson, Missouri in the US prepared on Wednesday for a grand jury report expected soon on the fatal August shooting of an unarmed black teen by a white policeman, an event that laid bare long-simmering racial tensions in the St Louis suburb.

The shooting of 18-year-old Michael Brown sparked weeks of sometimes violent protests. Many businesses have boarded up their windows as they expect another wave of demonstrations to follow the grand jury's decision, particularly if officer Darren Wilson is not charged.

Jimmie Matthews, who said he had lived in Ferguson for half a century, said he planned to protest against the grand jury's decision regardless of whether it brings charges.

"Whatever outcome they have, we're going to be protesting. Either way, the issues are the same," said Matthews, who is black. "We feel that we are not protected by anyone in the system."

More than two-thirds of the residents of Ferguson are black, but its mayor, police chief and most of its police department are white. Black residents say their conflicts with the police long predate Brown's shooting.

In a sign of tensions ahead of the grand jury report, a few dozen protesters gathered outside the city police station late on Wednesday in sub-freezing temperatures faced by officers in riot gear.

Some protesters chanted "Indict that cop." Police arrested about six people when protesters tried to block the street after ignoring orders to keep it clear. The arrests were the first of protesters in about a week.

On Tuesday, Missouri Governor Jay Nixon named a panel of 16 commissioners to develop solutions to the deep-seated socioeconomic disparities in and around Ferguson.

Despite the tensions, some in Ferguson have tried to carry on life as usual. A crew of city workers spent Wednesday morning putting up Christmas decorations on the street that is home to the Ferguson Police Department. Activists say that will be the first place demonstrators assemble after the grand jury report.

Officials have said the grand jury is expected to make its decision by the end of the month.

The Ferguson-Florissant School District told parents on Wednesday that schools may close early or not open at all on the day the grand jury's decision comes, with the decision based on when officials learn the report is coming.

Country singer Hunter Hayes, citing the state of emergency declared by the governor, canceled a concert scheduled for Thursday night at an arena on the campus of St. Louis University.

Nixon has defended his decision to declare the state of emergency ahead of the grand jury's decision, a move some called heavy-handed, particularly given that protests in recent days had been peaceful. The state of emergency allows the National Guard to deploy to the St. Louis area.

"For him to put Missouri into a state of emergency, to me it's a declaration of war on the protesters," a local activist and rapper who goes by the name T-Dubb-O said on a media conference call organized by activists. "We'll be treated as third-class citizens again when this decision is released and they don't like what we are doing."

St. Louis Mayor Francis Slay asked for 400 National Guard troops to be deployed to his city, to work in alternating 12-hour shifts at 45 locations around the city.

There are conflicting accounts of what preceded the August 9 shooting of Brown, with some witnesses contending he had raised his hands in surrender and others describing a struggle between the teen and Wilson.

(Reuters)